KNOWLEDGE, PERCEPTION, and USE of the KETOGENIC DIET in COLLEGE STUDENTS at a MIDWESTERN UNIVERSITY a Thesis Submitted to the Co

KNOWLEDGE, PERCEPTION, AND USE OF THE KETOGENIC DIET IN COLLEGE STUDENTS AT A MIDWESTERN UNIVERSITY

A thesis submitted to the college of Kent State University College of Education, Health, and Human Services in partial fulfillment of the requirements for the degree of Master of Science

Alexandria M. D’Agostino

May 2019

Thesis written by

Alexandria M. D’Agostino

B.S., Cleveland State University, 2017

M.S., Kent State University, 2019

Approved by

______, Director, Master’s Thesis Committee Eun-Jeong Ha

______, Member, Master’s Thesis Committee Natalie Caine-Bish

______, Member, Master’s Thesis Committee Tanya Falcone

Accepted by

______, Director, School of Health Sciences Ellen Gleckman

______, Dean, College of Education, Health and Human Services James Hannon

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D’AGOSTINO, ALEXANDRIA M.S., May 2019 Nutrition and Dietetics

KNOWLEDGE, PERCEPTION, AND USE OF THE KETOGENIC DIET IN COLLEGE STUDENTS AT A MIDWESTERN UNIVERSITY (PAGE 172 pp.)

Director of Thesis: Eun-Jeong Ha, Ph.D.

The ketogenic diet (KD) as a weight management method continues to gain popularity among college students because of its rapid weight loss results and quick health advantages (Abbasi et al., 2018). Despite the lack of KD knowledge represented among students (N=1,131) in the current study, students continue to engage in unhealthful eating behaviors such as fad diets (FD) (like the KD), thus failing to adopt healthy eating patterns (Pearson & Young, 2008). The purpose of this study was to examine KD knowledge, perception, and use among college students. Participants were limited to male and female students between the ages of 18-26 years who completed an online self-reported survey questionnaire. Results showed 18.1% of students responded to using the KD. Significant differences in KD knowledge were found between health related majors and non-health related majors (p=0.018), and between users and non-users

(p= 0.001). Overall, health related majors and users had higher knowledge scores versus non-health related majors and non-users. For perception, results indicated a significant three-way interaction effect between sex, health related major, and users (p=0.026).

Within each combination of user and major, male students perceived the KD as favorable than females, except for KD users in non-health related majors, where females had a slightly

higher perception than males. Future studies analyzing KD knowledge, perception, and use for weight management long-term are needed to confirm the results of this study.

ACKNOWLEDWEMENTS

I would like to thank my thesis advisor Dr. Eun-Jeong Ha for her guidance, endless support, and patience throughout this process. Without her encouraging feedback and advice, this study would not have been possible. I would also like to thank my committee members for their continuous support and feedback. Because of my committee members collaborative efforts, I was able to generate an extensive and comprehensive document addressing the ketogenic diet’s current role in weight management.

In addition, I would also like to thank Anthony Shreffler and Jordan Pastor over in the Research Bureau in White Hall for their guidance and dedication to my survey development and data analysis.

Lastly, I would like to thank my incredible family, friends and fiancé for their unceasing love and support throughout this journey. Thank you for believing in me, and for always reassuring me that I could accomplish anything I set my mind to.

TABLE OF CONTENTS

Page

ACKNOWLEDGEMENTS ...... iv

LIST OF FIGURES ...... x

LIST OF TABLES ...... xi

CHAPTER

I. INTRODUCTION ...... 1 Statement of the Problem...... 3 Purpose Statement ...... 4 Hypothesis ...... 5 Operational Definitions ...... 5

II. REVIEW OF LITERATURE ...... 7 Overweight and Obesity ...... 7 Prevalence in United States ...... 7 Factors Contributing to Obesity ...... 9 Genetics ...... 9 Lifestyle ...... 14 Dietary Intake ...... 14 Added-Sugar ...... 15 Added-Fat ...... 15 Eating Out ...... 16 Portion Sizes ...... 18 Snacking ...... 19 Physical Activity ...... 20 Basal Metabolic Rate ...... 22 Lean Muscle Tissue ...... 23 Environment ...... 24 Socioeconomic Status ...... 24 Geographic Location ...... 24 Education ...... 25 Chronic Diseases Related to Overweight and Obesity ...... 25

Type II Diabetes ...... 25 Prevalence ...... 26 Etiology/Causes/Mechanism ...... 26 Symptoms ...... 27 Complications ...... 27 Prevention & Treatment ...... 28 Cardiovascular Disease ...... 29 Prevalence ...... 29 Etiology/Causes/Mechanism ...... 30 Symptoms...... 30 Complications ...... 31 Prevention ...... 31 Treatment ...... 32 Hypertension ...... 33 Prevalence ...... 33 Etiology/Causes/Mechanism ...... 34 Symptoms ...... 35 Complications ...... 35 Prevention...... 35 Treatment ...... 36 Cancer ...... 37 Prevalence ...... 38 Etiology/Causes/Mechanism ...... 38 Symptoms ...... 40 Complications ...... 40 Prevention ...... 41 Treatment ...... 41 Other Health Outcomes Related to Overweight and Obesity ...... 43 Rheumatoid Arthritis...... 43 Prevalence ...... 43 Etiology/Causes/Mechanism ...... 44 Contrasting View ...... 44 Symptoms ...... 45 Complications ...... 45 Prevention ...... 46 Treatment ...... 46 Osteoarthritis...... 46 Etiology/Causes/Mechanism ...... 46

Symptoms ...... 47 Complications ...... 47 Prevention ...... 47 Treatment ...... 47 Depression ...... 48 Prevalence ...... 48 Etiology/Causes/Mechanism of How Depression May Cause Obesity ...... 48 Etiology/Causes/Mechanism of How Obesity May Cause Depression ...... 50 Symptoms ...... 50 Complications ...... 51 Prevention ...... 51 Treatment ...... 51 Gastrointestinal Complications ...... 52 Prevalence ...... 52 Etiology/Causes/Mechanism ...... 52 Symptoms ...... 53 Complications ...... 53 Prevention ...... 53 Treatment ...... 54 American Dietary Guidelines for Prevention of Chronic Disease ...... 54 Grains ...... 55 Vegetables, Legumes & Fruit ...... 56 Dairy ...... 57 Protein ...... 58 Fats/Oils...... 59 Weight Management ...... 60 Components of Successful Weight Management ...... 61 Weight Management Methods ...... 62 Prescription Diets ...... 63 Extreme Dieting/Fad Diets ...... 63 Surgery ...... 64 Medication ...... 64 Obesity in College Student Population ...... 65 Prevalence of Obesity Among College Students ...... 65 Factors Contributing to Obesity in College Students ...... 66 Newly Founded Independence ...... 66

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Lack of Time ...... 67 Academic Demands ...... 67 Social Life Demands ...... 68 Work Obligations ...... 69 Dietary Choices ...... 69 Fast Food Consumption/Dining Out ...... 70 Alcohol Consumption ...... 70 Lack of Nutrition Knowledge ...... 71 Credible Sources ...... 72 Non-credible Sources ...... 72 Overview of Fed vs. Fasted Metabolic States ...... 73 Overview of Macronutrients ...... 73 Carbohydrate ...... 75 Protein ...... 76 Fat ...... 77 Fed Metabolic State ...... 79 Fasted Metabolic State ...... 81 Overview of Fad Diets in College Students ...... 82 The Ketogenic Diet ...... 83 History and Original Use ...... 83 Current use of the Ketogenic Diet for Weight Management ...... 85 Types of Dietary Fat Consumed on the Ketogenic Diet ...... 85 Fats to Consume ...... 85 Fats to Avoid ...... 86 Different Types of Ketogenic Diets ...... 87 Classic Ketogenic Diet ...... 87 Modified-Atkins Diet and Low-Glycemic Control Treatment ...... 88 Medium-Chain Triglyceride Diet ...... 89 Ketogenic Diet for Weight Management Benefits ...... 90 Improved Hunger Cues ...... 90 Weight Loss ...... 91 Improved Blood Glucose Levels and HbA1C ...... 92 Improved Blood Lipid Profile ...... 93 Ketogenic Diet for Weight Management Issues ...... 94 Adherence & Compliance Issues ...... 94 Lack of Long-Term Health Outcomes ...... 95 Ketogenic Diet for Weight Management Short-Term Risks ...... 96

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Ketogenic Diet for Weight Management Long-Term Risks ...... 97 Nutritional Deficiencies ...... 97 Fatal Complications ...... 98

III. METHODOLOGY ...... 100 Purpose Statement ...... 100 Research Design ...... 100 Sample ...... 100 Measurement Instruments ...... 101 Qualtrics ...... 101 Procedures ...... 102 Statistical Analysis ...... 103

IV. JOURNAL ARTICLE ...... 105 Introduction ...... 105 Methodology ...... 107 Questionnaire ...... 107 Data Analysis ...... 109 Results ...... 109 Analysis of Ketogenic Diet Knowledge Among College Students ...... 111 Analysis of Ketogenic Diet Perception Among College Students...... 117 Discussion ...... 122 Ketogenic Diet Use Among College Students ...... 123 Ketogenic Diet Knowledge Among College Students ...... 125 Ketogenic Diet Perception Among College Students ...... 128 Limitations ...... 129 Application ...... 129 Conclusion ...... 130

APPENDICIES ...... 131 APPENDIX A. HEALTH RELATED MAJOR DESCRIPTION ...... 132 APPENDIX B. CONSENT FORM ...... 134 APPENDIX C. SURVEY QUESTIONNAIRE ...... 136

REFERENCES ...... 145

LIST OF FIGURES

Figure Page

1. Outline of the Pathways for the Catabolism of Carbohydrate, Protein, and Fat into Acetyl-CoA ...... 79

2. Conversion of Acetyl-CoA to Ketone Bodies and Interconversion of Identified Ketone Bodies ...... 84

LIST OF TABLES

Table Page

1. General Body-Fat Percentage Categories ...... 61

2. Mean Dietary Intake of Macronutrients in Adults Aged 20 Years and Older...... 74

3. Energy Equivalents Per Gram for each Macronutrient ...... 74

4. Structure of Long-Chain Fatty Acids ...... 78

5. Comparison of Daily Macronutrient Composition and Initiation Requirements Between Various Ketogenic Diets and the 2015-2020 Dietary Guidelines for Americans ...... 88

6. Demographic Characteristics of College Students Who Responded to the Ketogenic Diet Survey (N=1,131) ...... 110

7. Assessment of Ketogenic Diet Knowledge Among College Students Based on Self-Reported Survey Responses (N= 1,131) ...... 112

8. Assessment o Ketogenic Diet Knowledge In-Between Interaction Effects Among College Based on Self-Reported Survey Responses (N= 1,131) ...... 113

9. Assessment of Ketogenic Diet Knowledge by Question Among College Students Based on Self-Reported Survey Responses (N= 1,131) ...... 114

10. Mean Ketogenic Diet Perception Scores Among College Students Based on Self-Reported Survey Responses (N = 1,096) ...... 119

11. Assessment of Ketogenic Diet Perception Score In-Between Interaction Effects Among College Students Based on Self-Reported Survey Responses (N = 1,096) ...... 120

12. Assessment of Ketogenic Diet Perception Scores By Question Among College Students Based on Self-Reported Survey Responses (N = 1,096) ...... 121

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CHAPTER I

INTRODUCTION

The escalating overweight/obesity epidemic is a significant public health concern affecting a about half (about 93.3 million) of all adults living in the United States (U.S.)

(Center for Disease Control and Prevention, 2017). This data is concerning considering the harmful impacts obesity may attribute to a person’s health. Obesity is associated with the development of numerous chronic diseases such as, type 2 diabetes (T2DM), cardiovascular disease (CVD), hypertension (HTN), cancer, arthritis, as well as other negative health outcomes (Marcia, 2018; Schwartz, 2014).

The ongoing rise of obesity in the U.S. proposes many health risks to every age, one age group particularly at risk are college students. It has been estimated freshmen average weight gain is approximately 1.6 kg per year with a 1.2% annual increase in adiposity (Fedewa et al., 2014). Research shows if weight management is unaddressed in young adulthood, weight gain can be directly associated with increased weight in later adulthood (Swanson, 2015; Pollard, 2015). Factors contributing to overall energy imbalance among college students include lack of time, poor dietary choices, and lack of nutrition knowledge (Swanson, 2015). Although college students have been identified as an at-risk population for significant weight gain, college students seem to be more aware of their overweight/obesity risk and are taking the initiative to become more health conscious (Wing, 2003).

The internet as well as social media platforms, such as Facebook, Twitter,

Instagram, Pinterest, Public Blogs, etc., are among the most common sources of nutrition

information for Americans (Perrin, 2015). In 2015, up to 90% of U.S. young adults used social media, a 12% increase since 2005 (Perrin, 2015). With this data, college students

(with primary emphasis on young adults between the ages of 18-26) are more likely to engage in social media platforms, and therefore have an increased likelihood of being exposed to vast amounts of nutrition information (Perrin, 2015) One study found dramatic growth in use of the internet as a main source of nutrition and dietary information from 9.1% in 2004 to 33.7% in 2012 (Pollard, et al., 2015). Young adults appear to be utilizing the internet for weight management and show interest in knowing more ways of preparing healthy foods, knowing quicker ways of preparing healthy foods, more information to help decide if foods are healthy, and knowing more about cooking making it easier to follow a healthier diet (Pollard, 2015).

One typical health related solution promoted today (i.e social media, television, etc.) are Fad Diets (FD); or non-credible temporary diet solutions that promise weight loss or other health advantages. Popular FD include: Paleo Diet, Master Cleanse or

Detox Diets, Atkins Diet, Ketogenic Diet (KD) and more, all of which promise a quick solution for weight loss in a short period time (Obert et al. 2017). One increasingly popular FD for weight loss being the KD; or a high-fat, low-carbohydrate, moderate protein diet that aims to force the body to breakdown fat instead of glucose (The

Academy of Nutrition Dietetics, 2017). Although KD is primarily recognized as a FD,

KD was originally developed as a therapeutic treatment for patients suffering from epilepsy (Wheless, 2008). However, because of its’ short-term health outcomes and accelerated weight loss, KD continues to grow in popularity as a weight management

method (Paoli, 2014). It is important to note however, complications from the KD may arise if calories from fat are inappropriate with KD recommendations, if carbohydrate or protein consumption exceeds daily KD recommended intake, if the type of dietary fat consumed is not in line with KD recommendations, or if diabetic patients are diagnosed with severe insulin deficiency or insulin resistance. Disruptions to the diets course of action could alter future outcomes and overall health of the patient (Khandelwal et al.,

2017).

Statement of the Problem

College is a particular time when young adults face new challenges; some including difficulty with self-direction, and or regulation of competing demands

(Swanson, 2015). Because of these (as well as other) potential factors, students may struggle to balance their daily responsibilities and fulfill all their necessary demands.

Therefore, a healthy diet and regular exercise may seem unfeasible to young college students (Claxton & Wells, 2009). Current data supports this claim showing a significant increase in body weight among college students, putting them at risk for overweight and obesity (Swanson et al., 2015; Greaney et al., 2008; Yahia et al., 2016). Therefore, in effort to maintain a healthy weight, or achieve a desirable weight, college students are engaging in various types of weight loss methods. It seems many outside influences seem to strongly effect the direction students take in order to achieve their weight goals regardless of their own perception and beliefs (Pearson & Young, 2008). Among weight loss methods, FD such as the KD, have gained popularity due to rapid and easy-fix weight loss results (Obert et al. 2017; Abbasi, 2018). Consequently, despite the lack of

knowledge of these FD (understanding potential risks, other complications etc.), students continue to engage in FD, and therefore, fail to adopt healthful eating patterns (Pearson &

Young, 2008).

Like any other FD, KD imposes certain health risks such as gastrointestinal upset and nutrient deficiencies (Kang et al., 2004; Rogovik et al., 2010). Currently, there is a lack of long-term studies (>2 years) analyzing the long-term health risks associated with the KD. Scarcity of these studies propose many unanswered questions regarding clinical impacts, safety, tolerability, efficacy, duration of treatment, and prognosis after discontinuation of the diet (Gupta, 2017). In order to grasp a better understanding of college student’s general comprehension of KD, knowledge and perception should to be measured so researchers may (in the future if necessary) address and educate students on current factual versus misleading information regarding KD based on student self- reported survey responses. In addition, further research may allow college students to become aware of their perceived knowledge vs. actual knowledge regarding benefits and potential risk factors of the KD. Future research addressing these issues is important because it may increase knowledge and awareness of KD, and allow college students to make better informed, educated nutrition-related decisions.

Purpose Statement

The purpose of this study is to: 1.) examine college students’ knowledge and perception

of the ketogenic diet 2.) investigate college students’ use of ketogenic diet at a

midwestern university.

Hypotheses

Hypothesis 1: There is a difference in knowledge of ketogenic diet among health related majors vs. non-health-related majors.

Hypothesis 2: There is a difference in knowledge of the ketogenic diet among sexes.

Hypotheses 3: There is a difference in knowledge of the ketogenic diet among users vs non-users.

Hypothesis 4: There is a difference in perception of the ketogenic diet among health related majors vs. non-health-related majors.

Hypothesis 5: There is a difference in perception of the ketogenic diet among sexes.

Hypotheses 6: There is a difference in the perception of the ketogenic diet among users vs. non-users

Operational Definitions

College Students- Students between the ages of 18-26 attending Kent State University to obtain an undergraduate or graduate degree.

Ketogenic Diet- A high-fat, low-carbohydrate, moderate-protein diet that aims to force the body to breakdown fat and use ketone bodies as fuel instead of glucose.

Knowledge- An individual’s familiarity, awareness, and understanding of the ketogenic diet by means of fact, information, and research as evidence by a self-reported true and false survey questionnaire.

Perception- An individual’s beliefs, feelings, and attitude towards the ketogenic diet as measured by a self-reported 5-point Likert Scale survey questionnaire.

Health Related Majors- Students following an academic plan to obtain one or more degree associated with health at Kent State University. Major descriptions can be found in appendix A.

Non-Health Related Majors- Any student following an academic plan to obtain a degree that is not included in the health related majors at Kent State University.

User- Students who have used the ketogenic diet as evidence by a self-reported survey questionnaire.

Non-User- Students who have never used the ketogenic diet as evidence by a self- reported survey questionnaire.

CHAPTER II

REVIEW OF LITERATURE

Overweight and Obesity

Body Mass Index (BMI) is a person's body weight in kilograms divided by the square of height in meters. A high BMI can be a direct indicator of high body fatness and increase various risk factors associated with chronic illnesses. A healthy (or “normal”)

BMI can be defined as 18.5 to <25, where a BMI 25 to <30 falls within the overweight range, a BMI of 30 is considered to be obese (grade 1), with severe and morbid obesity defined as BMIs of 35 to <40 (grade 2) and 40 (grade 3), respectively. (Centers for

Disease Control and Prevention (CDC), 2016; Meldrum et al., 2017).

Prevalence in the United States

According to the latest figures from the CDC, obesity in the United States (U.S.) is a significant public health problem. The most recent data available from the CDC’s

2017 Behavioral Risk Factor Surveillance System (BRFSS) states that the presence of obesity in Americans ranges from 22.5% (Colorado) to 38.1% (West Virginia), thus failing the Healthy People 2015-2020 objective of reducing the proportion of adults who are both overweight and obese (Ward-Smith, 2010). This data suggests Americans continue to struggle with overweight and obesity. A recent study from 2005 to 2014 showed the prevalence of obesity among women increased from 35% to 40% and severe obesity increased from 7% to 10%, whereas among men, the prevalence of obesity increased from 33% to 35% and severe obesity increased from 4.2% to 5.5% (Hales,

2018).

Although there is a large prevalence of overweight and obesity in the U.S. as a whole, certain regions and individual states seem to have experienced slightly higher increases. States in the South have the highest prevalence of obesity (32.4%), followed eight by the Midwest (32.3%), the Northeast (27.7%), and the West (26.1%). Presently, there are two states, Mississippi and West Virginia, with a prevalence of obesity of greater than or equal to 35% (Centers for Disease Control and Prevention, 2017).

Moreover, supplementary data to these findings also indicate out of the 47 states, 24 states had significantly higher rates of obesity among nonmetropolitan county residents than among metropolitan county residents in all U.S. Census regions, including all 50 states, and the District of Columbia (Centers for Disease Control and Prevention, 2018).

The prevalence of overweight and obesity also varies when analyzing specific ethnic/racial groups along with correlating socioeconomic status (SES) in the U.S. Data collected from 2015-2017 compared obesity rates with SES/income levels of: non-

Hispanic white, non-Hispanic black, and Mexican-American men and women. Results found the prevalence of obesity is generally similar at all income levels, with a tendency to be slightly higher at higher income levels in men (33% of men who lived in households with incomes at or above 350% vs. 29.2% of men who lived below, and

130% of the poverty level were obese). Among women, the prevalence of obesity seemed to increase as income decreased (29.0% of women who live in households with income at or above 350% of the poverty level were obese and 42.0% of those with income below 130% of the poverty level were obese). Lastly, trends examined between education level and obesity rates indicated no significant correlation between education

level and obesity prevalence among men, while obesity prevalence increased as education decreased among women with highest rates of obesity present in non-Hispanic black women (National Health and Nutrition Survey, 2010).

Factors Contributing to Obesity

The exact cause of obesity is unknown; however, there appears to be a complex relationship among biologic, psychosocial, and behavioral factors, which include genetic makeup, dietary behavior, physical activity, and environment (Apovian, 2016).

Genetics

Since the sequencing of the human genome, researchers and geneticists have begun to document the interactions among genetic and environmental risks as precursors to chronic illnesses including the influence of gene-diet interactions in disorders such as obesity (Johnson et al., 2006). Genetics, or the study of how individual genes or groups of genes composed of DNA (deoxyribonucleic acid) are involved in health and disease and provide the informational basis of all underlying processes and structures of life

(Center for Disease Control and Prevention, 2017; Griffiths et al., 1999). In recent decades, attention has shifted its’ focus to studying the interactions between genetic and environmental factors such as: diet and lifestyle, over-nutrition and sedentary behavior, in promoting the progression and pathogenesis of polygenic diet-related diseases such as metabolic syndrome, T2DM and CVD. For example, one study identified heritability rates estimated between 10%–30% for metabolic syndrome, indicating that these conditions are partly heritable (Phillips et al., 2013). Studies identifying complex differences among identical twins have also provided a unique opportunity to disentangle

lifestyle and environmental factors on the human system. One study found once identical twins, who share the exact same genetic makeup, were exposed to a myriad of external environmental influences, significant differences in their phenotypes were identified.

This study demonstrated even in twins, genotypes may be altered and significantly influenced by behavioral preferences such as dietary intake causing differences in observable characteristics (Pallister et al., 2014). In addition to environmental influences altering the biological genome, the inverse of this proposes many plausible questions as well: how the evolution of altered genomes reacts to various dietary sources, and how this influences an individual’s dietary preferences. The recognition that nutrients have the ability to interact and modulate molecular mechanisms underlying an organism's physiological functions has prompted a revolution in the field of nutrition. This leads to the creation of nutrigenomics and nutrigenetics, two fields with distinct approaches to elucidate the interaction between diet and genes with a common ultimate goal to: optimize health through personalization of diet, and to provide powerful approaches to unravel the complex relationship between nutritional molecules, genetic polymorphisms

(genetic variations), and the biological system as a whole (Mutch et al., 2018).

Although these two concepts are intimately associated, they take a fundamentally different approach to understanding the relationship between genes and diet. Definitions of each term are as follows:

- Nutrigenomics aims to determine the influence of common dietary ingredients

on the genome and attempts to relate the resulting different phenotypes

(observable characteristics or traits) to differences in the cellular and/or genetic

response of the biological system

- Nutrigenetics aims to understand how the genetic makeup of an individual

coordinates their response to diet, and thus considers underlying genetic

polymorphisms (Mutch et al., 2018).

As previously mentioned, nutrigenomics offers a possibility to unravel the effects of diet on health. Nutrigenomics explains why people of different genotypes (genes in

DNA responsible for a particular trait) might respond to environmental changes quite differently. According to recent studies, nearly one-thousand genes have been associated with human disease, and over four-hundred genes have been directly and indirectly associated with human obesity (Huang et al., 2003; Johnson et al. 2006). One study found dietary saturated intake greater than 12.6% modified the effect of the FTO rs9939609 gene increasing the risk of obesity in carriers of that altered gene. Another study demonstrated that the genetic association with adiposity was stronger among participants with higher intake of sugar-sweetened beverages and fast food, than among those with lower intake (Huang et al., 2013). Recently, researchers have identified the first grouping of genes considered to genetically regulate processes and mechanisms that contribute to body weight homeostasis, they include: physical activity, appetite, adipocyte differentiation, insulin signaling, mitochondrial functions, lipid turnover, thermogenesis, and energy efficiency. They grouped genes according to how they

regulate metabolic functions, in which there are polymorphisms that have been related to genetically mediated differences to dietary weight loss interventions:

- Regulating energy intake (e.g., MC3R, MC4R, POMC, LEP, LEPR, FTO)

- Lipid metabolism and adipogenesis (e.g., PLIN1, APOA5, LIPC, FABP2)

- Thermogenesis (e.g., ADBRs, UCPs)

- Adipocytokine synthesis (e.g., ADIPOQ, IL6)

- Transcription factors (e.g., PPARG, TCF7L2, CLOCK) (Joffe et al., 2016;

Mutch et al., 2018).

These studies provide examples of how differences in an individual’s response to diet have been attributed to differences in the underlying genetic makeup, prompting exploration into the role of nutrient-gene interactions in the determination of a healthy phenotype (Joffe et al., 2016; Mutch et al., 2018).

Nutrigenetics, in the context of nutritional biochemistry, may provide a deeper understanding of the impacted biochemical pathways responsible for facilitating particular dietary-related behaviors (Joffee et al., 2016). In essence, nutrigenetics aims to understand how the genetic makeup of an individual coordinates the response to diet. If the human population were genetically identical and lived in a constant environment, then responses to diet and drugs would be equivalent; however, this is clearly not the case

(Mutch et al., 2018). One study showed individuals carrying a specific allele of a branched-chain amino acid (FTO variant rs1440581 gene) benefited less in weight loss than those without this allele when undertaking an energy-restricted high-fat diet. Where those who were carrying the gene, a high-protein diet was found to facilitate weight loss

and improvement of body composition in individuals with the risk allele of the gene, but not in other genotypes (Huang et al., 2013). Another example of the complex interactions between genetics, diet and disease found a stronger relationship existed between the risk of developing disease and the consumption of peanut butter contaminated with aflatoxins among Sudanese people with a specific genotype, compared to those lacking the genotype (Sharma et al., 2017).

The potential influence of nutrients on the genome cannot be underestimated; however, there are certain genes that have a heightened sensitivity to diet (often referred to as “candidate” or “susceptibility” genes) such as:

- Genes that are chronically activated during a disease state and have been

previously demonstrated to be sensitive to dietary intervention.

- Genes with functionally important variations.

- Genes that have an important hierarchical role in biological cascades.

- Polymorphisms that are highly prevalent in the population.

- Genes with associated biomarkers, rendering clinical trials facile (Mutch et al.,

2018; Johnson, 2006).

Although scientists have only brushed the surface of this research, steps have been taken to investigate future genetic polymorphisms/variations associated with increased risks of developing certain chronic illness. This method of chronic illness prevention may help reduce overall nutrition-related disorders (such as obesity) by providing education to participants on the hazardous behaviors associated with escalated risk factors (Mutch et al., 2018; Johnson, 2006).

Lifestyle

Obesity has been attributed to excessive calorie consumption in relation to the work expended. Popularly expressed as “calories in, calories out” this concept addresses how creating a deficit could cause weight loss, whereas excess, regardless of macronutrient type or quality (or decreasing energy expenditure), could lead to weight gain (Howell et al., 2017).

Dietary Intake. Excessive calorie consumption similarity known as “over eating,” continues to be a main contributor to adiposity. Currently, there are food products that are highly available at low cost promoting excessive calorie intake (Meldrum et al.,

2017). These foods include highly processed foods and fast foods that are usually high in added-sugar and added-fat (Castillon et al., 2012). Excessive consumption of foods high in added-sugars and added-fat (saturated and trans fats) coincide with weight gain by significantly increasing the calorie content in various food items, making them calorie dense, but not necessarily nutrient dense. Such food items continue to be promoted in restaurants and other food outlets, increasing the likelihood of consumers engaging in such dietary behavior (Heart Advisor, 2015). Periodically sold and favored items high in added-sugar intake include sugary soft drinks, bakery products, and sugar directly added to coffee and other beverages. Foods high in added-fat (especially saturated fat) include cured cheese, bakery products, red meat, raw-cured sausages, and whole milk. Main sources of both added-fat and added-sugars include bakery items such as cookies, muffins and pastries” (Castillon et al, 2013). One example of how added-sugar and added-fat can contribute to excessive calorie intake is by analyzing nutrition differences

in a regular cup of coffee vs. Starbucks specialty coffees. Starbucks has over 22,000 locations in the U.S. and is a popular choice when it comes to coffee drinkers. Coffee alone has zero calories and contains zero grams of sugar and fat. However, after adding large amounts of sugar and fat, a Starbucks caramel Frappuccino blended coffee, contains

420 calories, 66 grams of sugar and 15 grams of fat (Starbucks, 2019).

Added-Sugar. Excess intake of added-sugar is known to be associated with poor- quality diets, and excessive calorie consumption. Added-sugars can be defined as sugars added to foods by the manufacturer, cook or consumer (sugars naturally present in honey and syrup) that do not include intrinsic or naturally occurring sugars that are, for example, within cell walls of intact fruits, vegetables and berries (Kaartinen et al., 2017).

Adding sugar is the least expensive way that the food industry can make everything tastier to increase sales (Meldrum et al., 2017). Before 1900, sugar was a rare treat. The average per-person consumption of sugar in the U.S. increased from 4–6 pounds per year in the early 1800s to 150–170 pounds today (Meldrum et al., 2017). Although recommendations limit daily calories from added-sugars to <10% of total calories consumed, current data shows in the U.S., consumption patterns typically exceed these levels, accounting for 13% of total energy intake (Davy et al., 2017).

Added-Fat. In addition to added-sugars, food items today have higher contents of added-fat (especially saturated and trans-fat). Dietary fat is the most concentrated source of dietary energy providing 9 kcal per gram, and contributes to the texture, flavor, and aroma of a wide variety of foods, making individuals more likely to choose these items

(Drewnowski et al., 2010). When fat is added to foods, it significantly increases the

calorie content. For example, a medium-sized baked potato contains approximately 160 calories, 30 grams of carbohydrate, and 2 grams of fat (American Heart Association, &

Acadamey of Nutrition and Dietetics, 2014). However, when the same item is saturated in oil and converted to french fries, both the calories and fat content dramatically increase. This example exhibits how added-fat increases the total calorie and fat content in foods. Recommendations for daily fat intake range between 20%-35% of daily calories where <10% are from saturated fat (The Academy of Nutrition and Dietetics,

2014). In the U.S., dietary fat accounted for 33%–36% of dietary energy, where the average medium intake of saturated fat was approximately 11.1% (Drewnowski et al.,

2010). This data exemplifies how fat consumption is significantly greater than the recommended intake. One ubiquitous barrier to reducing fat consumption is due to the undeniable sensory appeal of foods containing high amounts of added-sugars, added-fats, and salt (Heart Advisor, 2015). Companies (such as food markets/grocery stores and restaurants/fast-food chains.) have become aware of these high-fat, high-sugar food preferences, and as a result, continue to emphasize sales of these items to drive business

(Drewnowski et al., 2010).

Eating Out. In particular, meals from independent takeaway outlets are inconsistent with dietary recommendations, delivering portions that are high in energy, all macronutrients and sodium (Goffe et al., 2017). One study found that 36% of

American adults consumed fast food daily in 2007–2008, which resulted in the intake of

877 calories per day from fast food alone (Powell et al., 2012). Portion sizes of many foods from takeaway outlets has also increased since the mid-1980s and, consequently,

increased in calories (Nestle, 2003). “In 2007–2008, 33%, 41% and 36% of children, adolescents and adults, respectively, consumed foods and/or beverages from fast-food restaurant sources and 12%, 18% and 27% consumed from full-service restaurants

(Powell et al., 2012). Since the contribution of away-from-home foods to the diet is increasing, and since their nutritional profile is generally worse than foods prepared at home (more fat and saturated fat, less calcium, fiber and iron), Americans are at greater risk of becoming obese by poor nutrition habits (Strumpf, 2004; Shaihk et al., 2015).

Recent studies have identified various reasons for the rise in “dining-out” including: Physiological/biological needs where most people dine out in restaurants because they are fundamentally hungry and needs a restorer. Social dining where people dine at restaurants because it has become a status symbol and allows people to enjoy leisure time spent with others of interest. Esteem/psychological needs where esteem needs are stimulated through the heightening of self-esteem and fulfilling lifestyle needs or through the intake of delicious dishes. Others believe that people eat out for status purpose or a treat for celebration. Convenience needs of eating out eliminates the stresses and time of food preparation and cooking. Others are unable to get home for meals, have no knowledge and skill to prepare the food they like, or have no one is available at home to prepare meals for them. Business needs may be fulfilled by conducting meetings that end with a lunch or dinner in a chosen restaurant depending on the level of business. Some people eat out basically to impress their guests by taking them out. Healthy reasons for eating out is based on the nutritious and nourishing food options that are available in restaurants. People now decide to dine in restaurants because

they are prepared to pay a premium price for high quality (Ghana, 2016; Jones, 2002).

And lastly, a lack of cooking skills/preparation space may disable individuals from preparing meals at home due to a lack of cooking knowledge and skills to prepare meals.

In addition, some may not have access to space or facilities available for meal preparation

(Jones, 2002).

Portion Sizes. From the consumer’s perspective, larger portions may appear as a bargain, but such meals are typically prepared with high-fat ingredients such as butter, cream, or oils, and contains high amounts of added-sugars and salt (Cohen et al., 2014;

Heart Advisor, 2015). Consumers unable to recognize large portion sizes may continue to practice similar eating behaviors at home, and furthermore, increase their risk of becoming obese. In the U.S., less than 15% of total grain consumption is from whole grain sources and only 6–8% of adults meet the target of three whole-grain servings per day (Williams, 2012). A whole grain consists of three botanically defined parts: the bran, the germ, and the endosperm. The bran and germ contain many nutrients and phytochemicals, whereas the endosperm is largely starch and provides mostly energy. A refined grain contains only the endosperm and thus provides fewer nutrients and phytochemicals than does the whole grain. U.S. adults consume on average 5.7 servings of refined grain/day despite the well-known fact that whole-grain food is more nutrient dense than is refined-grain food (Steffen et al., 2003). This increasing consumption of added-sugar and refined grains comprises the other 85% of total grain consumption and proposes numerous health risks such as obesity and nutritional deficiencies. One key component removed in the refined processing is fiber; a nutrient that has been shown to

slow digestion and increase satiety (Gropper & Smith, 2013). Removing this nutrient may reduce satiety cues and therefore potentially lead to excessive overconsumption.

Several prospective studies have also shown reduced disease incidence with increased consumption of whole-grain foods; reasoning behind this could be because these foods contain high concentrations of vital vitamins and minerals such as B Vitamins and fiber

(Ludwig et al., 2011). However, in refined grains, various nutrient-dense structures are removed thereby delivering minimal nutritional benefits. Examples of refined items include refined cereal grains (e.g., white rice, polenta, semolina, couscous), pasta, and bread from white or rice flour (i.e., not whole-grain varieties).

Snacking. One contributor of excessive calorie consumption stems from immoderate snacking. Snacking is often defined as consuming a food or drink between regular meals; however, this definition varies somewhat, with some studies defining specific periods of time after a meal and others specifying the amounts of food (e.g., portion sizes smaller than regular meals) or calories consumed (Hess et al., 2016).

Studies reveal that American children are consuming upward of three snacks per day, accounting for more than 27% of daily energy (Piernas & Popkin, 2010). Snacking does not directly imply excessive calorie consumption; but rather the type of snack, and amount of snacking that contributes to rise of obesity rates (Hess et al., 2016). On a beneficial side, observations suggest that in healthy individuals, snacking improves the macronutrient content of the diet without adding energy to it (Bellisle, 2014). In today's society, however, snacking contributes close to one-third of daily energy intake, with many snacks consisting of energy-dense and nutrient-poor foods (such as processed food

items) (Njike et al., 2016). Dietary surveys in young American adults also indicate that the added daily energy load from snacks has increased by 261 kcal for men and 160 kcal for women (Piernas et al., 2010). Common snack foods identified among the US population contributing to excessive calorie intake - that are energy-dense, nutrient-poor, high in sodium, sugar, and/or fat - include cookies, cakes, sugar-sweetened beverages, and chips (Hess et al., 2016). Among U.S. adults, the number of daily snacking occasions has increased by 1 snack/day from 1997 to 2006 (Piernas et al., 2010). Thus, because snacks are pervasive in today’s society, with energy-dense snacks and snacks of low dietary quality, poor or excessive snacking may contribute to obesity risk (Njike et al., 2016, Bellisle, 2014). This type of snacking constitutes an unquestionable risk factor for adiposity since the high energy intake from snacks is not compensated at other eating times (e.g. regular meals) (Bellisle, 2014).

Physical Activity. Physical inactivity or sedentary behavior is a primary contributor to the obesity epidemic (Gray et al., 2018). Sedentary behavior, or “leisure- time” physical inactivity such as sitting or watching television, is encouraged given availability and popularity of computers, television, and other electronic devices such as smart phones, which continue to promote physical inactivity (Center for Disease Control and Prevention, 2013). Recent studies suggest “sedentary behavior has increased at the population level from the 1960s, where the average sedentary time has increased from 26 hours per week in 1965 to 38 hours in 2009” (American Heart Association, 2016).

Currently, adults spend an average of six to eight hours per day in sedentary time, and adults >60 years of age average 8.5 to 9.6 hours per day in sedentary time (Clemes et al.,

2014). Today, the urban environment has many physical features that reduce the need for physical activity, such as elevators, escalators and other labor-saving devices (devices that save on energy expenditure such as motorized vehicles), along with passive entertainment such as video games, TV watching, and online news, socialization, and entertainment (Meldrum et al., 2017). In addition, some may be uninformed of the health benefits associated with daily physical activity, have limited time to dedicate to exercise, or simply have no place to exercise (American Heart Association, 2016). Together, these issues numerous propose obstacles when trying to adhere to daily physical activity recommendations.

Widespread inactivity makes continued efforts in physical activity promotion a persistent challenge. The precise content of physical activity recommendations is not broadly known, and there are concerns that the general messaging of the guidelines may seem unattainable for and even actually discourage currently inactive people (Füzéki et al., 2018). However, guidelines established by The U.S. Department of Health and

Human Services’ provide science-based guidelines to help children and adults in the U.S. improve their health through appropriate physical activity.

Recommendations for aerobic activity, muscle-strengthening, and bone- strengthening recommendations are as follows: For substantial health benefits, adults should do at least 150 minutes (2 hours and 30 minutes) a week of moderate-intensity, or

75 minutes (1 hour and 15 minutes) a week of vigorous-intensity aerobic activity, or an equivalence combination of moderate- and vigorous-intensity aerobic activity. Aerobic activity should be performed in episodes of at least 10 minutes, and preferably, it should

be spread throughout the week. For additional and more extensive health benefits, adults should increase their aerobic physical activity to 300 minutes (5 hours) a week of moderate-intensity, or 150 minutes a week of vigorous-intensity aerobic physical activity, or an equivalence combination of moderate- and vigorous-intensity activity. Additional health benefits are gained by engaging in physical activity beyond this amount. Adults also should do muscle-strengthening activities that are moderate- or high-intensity and involve all major muscle groups on 2 or more days a week, as these activities provide additional health benefits.

Basal Metabolic Rate. Physical activity helps prevent excess weight gain and or helps maintain weight loss in various ways. First, physical activity is associated with a higher Basal Metabolic Rate (BMR) (Kenney et al., 2015; Anders et al., 1996). BMR can be defined as the standardized measure of energy expenditure at rest, or, in other words, calories burned at rest. A higher BMR, hence, contributes to more calories burned during physical inactivity. “Because muscle (or lean muscle tissue) has high metabolic activity,

BMR is directly related to an individual's fat-free mass. Women typically have lower fat- free mass and greater percent body fat than men, thus, is partially why women tend to have a lower BMR than men of similar weight” (Kenney et al. 2015). Furthermore,

BMR is also directly affected and improved by frequency of physical activity. Data from a study analyzed BMR from endurance athletes (4 female and 4 male), at least 39 hours after their last training session. In comparison with sedentary nonathletic controls matched for sex and fat-free mass, athletes had a 13% higher BMR compared to the control (Anders et al., 1996). Another study analyzed the effects of either resistance or

endurance training on BMR in sixteen obese adolescent boys for six months. Results showed a significant decrease in body fat percentage and an increased BMR increased by

14.75% (Yetgin et al., 2018).

Lean Muscle Tissue. Regular physical activity, especially resistance-exercise training, helps promote lean muscle tissue growth and decreases adipose (fat) tissue accumulation. Resistance training, also known as “strength or weight training” encompasses a wide range of training modalities including body weight exercises, use of elastic bands, plyometrics, and hill running (Fleck & Kraemer, 2014). This type of exercise stimulates lean muscle tissue synthesis - with higher peaks in the untrained state than in the trained state - resulting in greater overall muscle protein synthesis in the untrained state. Several studies have found that resistance training not only promotes lean muscle tissue growth, but also encourages weight loss. One study found after following an eight-week resistance training regime (delivered 3 times weekly at roughly

60% of their one-rep max), found a significant change in participants’ overall body mass

(weight), percentage of body fat (−13.05%), lean muscle tissue (+5.05%), and fat mass

(−12.11%) when compared to the control group (Shaw, 2006). This study supports the relationship between resistance training and its effects on weight, body fat percentage, lean muscle tissue. Physical activity plays a key role in overall weight management and weight loss, but it is important to note, exercise alone may not be enough to yield significant results. Referring back to the “calories in, calories out” concept, even when individual engage in daily physical activity, if calories consumed exceed calories expended, fat mass continues to accumulate (Fleck & Kraemer, 2014).

Environment. Environmental factors such as SES, geographic location, and education may also significantly impact overall health status and increase a person’s risk of becoming overweight or obese.

Socioeconomic Status. As previously mentioned, SES can have a significant impact on health status. Research shows social background has the greatest influence on the amount of physical exercise, impairment due to disorders, and the number of chronic conditions (Burkert, Rásky, et al., 2013). According to a few other studies, people of low

SES show an increased prevalence of morbidity, have higher level of health complaints, and have a lower life expectancy by seven years (Mackenbach, 2006; Currie et al., 2009).

In addition, obese individuals with a low SES self-report worse self-perceived health and quality of life (Mackenbach, 2006). These studies, therefore, suggest SES may be a strong predictor of obesity risk and overall health status.

Geographic Location. According to the above sections, specified geographic locations in the U.S. have shown to have higher obesity risks (Centers for Disease

Control and Prevention, 2018). In addition, research suggests people living in socioeconomically deprived areas were less likely to see their area as conducive to healthy behaviors, compared with residents of wealthier areas. The researchers noted significant variations in the presence of food outlets, outdoor recreation facilities and green spaces between the cities surveyed. Residents who reported higher levels of social integration also rated their health more highly, were less likely to be obese and consumed more fruit (Brazier, 2016).

Education. Education may also play a major role in health status and obesity risk.

According to multiple studies, individuals of a low SES are found to have lower levels of education and have the highest prevalence of obesity, where the lowest prevalence of obesity is found among the highest educational bracket (Burkert, Freidl et al., 2013;

Toschke et al., 2005). One study proposes the relation between education and various health risk factors - smoking, drinking, diet/exercise, use of illegal drugs, household safety, use of preventive medical care, and care for hypertension and diabetes – is a very strong gradient, where the better educated have healthier behaviors along virtually every margin. In the end, data shows those with more years of schooling are less likely to smoke, to drink heavily, to be overweight or obese, or to use illegal drugs (Picker, 2019).

Chronic Diseases Related to Overweight and Obesity

In the U.S. chronic diseases are the main cause of poor health, disability, and death, and account for most of health-care expenditures (Bauer et al., 2014). The chronic disease burden in the U.S. largely results from factors such as poor diet and physical inactivity. Chronic diseases such as type 2 diabetes (T2DM) , cardiovascular disease

(CVD), chronic respiratory disease, hypertension (HTN), cancer, and metabolic syndrome accounted for nearly two-thirds of deaths worldwide. These as well as various others are identified as main causes of poor health, disability, and death, and account for most of health-care expenditures (Bauer et al., 2014).

Type 2 Diabetes

T2DM can be defined as a chronic condition that affects the way your body metabolizes sugar (glucose), your body's important source of fuel (Mayo Clinic, 2018).

In T2DM, the body doesn't respond well to insulin produced by the pancreas. This ill response to insulin results in high blood sugar levels because the glucose is unable to enter the cells. If glucose is able to enter the cell, blood sugar continues to rise and dismantles overall homeostatic environments (American Diabetes Association, 2015).

Prevalence. T2DM has become a highly prevalent disease all over the world and recognized as a worldwide epidemic. The global epidemic of obesity largely explains the dramatic increase in the incidence and prevalence of T2DM over the past 20 years.

Currently, over a third (34%) of U.S. adults are obese and over 11% of people aged ≥20 years have diabetes, a prevalence projected to increase to 21% by 2050 (Eckel et al.,

2011). This data parallels the aging and body mass index (BMI) of the population, thus confirming the relationship between obesity and T2DM (Servan, 2013).

Etiology/Causes/Mechanisms. Obesity is recognized as a primary cause of

T2DM. Typically, patients with T2DM are overweight or obese, which likely plays a key role in the disease manifestation (Eckel et al., 2011). Obesity (abdominal obesity, more specifically) induces insulin resistance and involves a plethora of molecules that predispose individuals to an inflammatory state and metabolic complications. At least three distinct mechanisms have been proposed to link obesity to insulin resistance and predispose to T2DM:

1) Increased production of adipokines/cytokines, including tumor necrosis

factor-α, resistin, and retinol-binding protein 4, that contribute to insulin

resistance as well as reduced levels of adiponectin.

2) Ectopic fat deposition, particularly in the liver and perhaps also in skeletal

muscle, and the dysmetabolic sequelae.

3) Mitochondrial dysfunction, evident by decreased mitochondrial mass and/or

function. Mitochondrial dysfunction could be one of many important underlying

defects linking obesity to diabetes, both by decreasing insulin sensitivity and by

compromising β-cell function (Kahn et al., 2013).

Mechanisms causing T2DM vary depending on the severity of obesity, as well as the type and location of fat accumulation (Cnop et al., 2002) Visceral fat, a type of body fat that’s stored within the abdominal cavity, is actively seen to increase the risk of serious health problems such as T2DM. One study identified a proportion of abnormalities are explained by visceral adiposity, especially that located within the abdominal cavity

(Eckel at el., 2011). Another study found that which each standard deviation increases of visceral fat, individuals had an 80% increased risk of being insulin resistant; eventually leading to a T2DM diagnosis (McLaughlin et al., 2011).

Symptoms. Signs and symptoms of T2DM often develop slowly. Common symptoms include: polyuria, excessive thirst, increased hunger, fatigue, blurred vision, slow-healing soars or infections, and areas of darkened skin (Mayo Clinic, 2018).

Complications. Complications arise when the body does not respond to insulin allowing glucose to build up in the blood instead of going into cells. This causes one of two problems: 1.) cells may be starved for energy, and or 2.) high blood glucose levels may directly cause complications with organs such as eyes, kidneys, nerves or heart

(Servan, 2013; The American Diabetes Association, 2015). Diabetic nephropathy, neuropathy, and retinopathy are the main microvascular complications induced by

chronic hyperglycemia via several mechanisms such as the production of advanced glycation end products (AGEs), the creation of a proinflammatory microenvironment, and the induction of oxidative stress (Papatheodorou,et al., 2016).

Prevention & Treatment. Lifestyle changes to reduce body weight has always been a mainstay of T2DM therapy. The Look AHEAD (Action for Health in Diabetes) foundation emphasizes intensive alterations in dietary intake (such as lower carbohydrate diets), and daily physical activity to promote insulin sensitivity and decrease risk of developing T2DM. One study found with weight loss a greater proportion of subjects achieved either partial or complete diabetes remission, had improved glucose control, required fewer glucose-lowering agents, including insulin, and a had greater proportion of participants achieved a HbA1c <7% (Look AHEAD, 2011; Ew et al., 2012). Although these findings demonstrate how dietary and physical behavior may attribute to T2DM prevention, the slowing or remission of the disease ultimately depends on the individuals impaired glucose tolerance and/or current stage of disease progression (Kahn et al.,

2012).

According to the CDC, treatment or management of T2DM requires a variety of thorough lifestyle changes. The American Diabetes Association recommends a carbohydrate-controlled diet to maintain and regulate blood sugar levels. Although diet specificities ultimately depend on the patient, typical recommendations include: <130 g/day carbohydrate, 14 g ﬁber/1000 kcal, cholesterol <200 mg/day, 20% protein (Khazrai et al., 2014). Healthy dietary behaviors, daily or frequent physical activity, prescribed medications such as insulin, other injectable or oral pharmaceuticals, all may be required

to help control blood sugar levels and avoid further complications of patients with

T2DM.

Cardiovascular Disease

CVD can be defined as any disease of the heart and blood vessels, including numerous problems many of which are related to a condition known as atherosclerosis.

Atherosclerosis is a condition that develops when a substance called plaque builds up in the walls of the arteries. This buildup narrows the arteries, making it harder for blood to flow through. If a blood clot forms, it can block the blood flow causing a series of health complications (American Heart Association, 2017). CVD includes all disorders of the heart and blood vessels such as: HTN (high blood pressure), coronary heart disease (heart attack), cerebrovascular disease (stroke), peripheral vascular disease, heart failure, rheumatic heart disease, congenital heart disease, and cardiomyopathies (Central Disease

Control and Prevention, 2018).

Prevalence. According to The World Health Organization (WHO) CVD is the number one cause of death globally. Estimates indicated 17.3 million people died from

CVDs in 2008, representing 30% of all global deaths. By 2030, almost 23.6 million people will die from CVD, mainly from heart disease and stroke. In U.S. adults ages 18 years and older, weight status is related to prevalent CVD risk. About two-thirds (66.6

%) of U.S. adults, including more than half (56.1%) of normal weight adults (BMI 18.5 -

<25 kg/m2 ), have one or more CVD risk factors (including type 1 diabetes and T2DM,

HTN, or dyslipidemia, or self-reported smoking (Dietary Guidelines Advisory

Committee, 2015).

Etiology/Causes/Mechanisms. CVD is causes by a plethora of factors such as high blood pressure, high cholesterol, high-fat combined with carbohydrates, T2DM, alcohol consumption, stress, and smoking (Mayo Clinic, 2018). Some of these factors have also been found in individuals suffering from obesity, establishing a relationship between the illness and increased CVD risk (Center for Disease Control and Prevention,

2013). According to the classic ‘diet-heart’ hypothesis, high intake of saturated fats and cholesterol and low intake of polyunsaturated fats increases the level of serum cholesterol, which leads to the development of atheromatous plaques. This accumulation narrows the coronary arteries, reduces blood flow to the heart muscle and brain

(increasing likelihood of a stroke), increases blood pressure, and therefore increases the risk of a heart attack (Dietary Guidelines Advisory Committee, 2015). This evidence suggests that behaviors such as poor dietary habits in conjunction with physical inactivity, and genetic predisposition, are associated with cardiometabolic risk factors

(Wang et al., 2017). CVD risk factors include elevated LDL-cholesterol, LDL oxidation, high blood pressure (BP), impaired glucose-insulin homeostasis, other altered lipoprotein concentrations and function, oxidative stress, increased visceral adiposity, inflammation, and more (Mozzaffairan, 2016; Wang et al., 2017).

Symptoms. There are many different types of cardiovascular disease. Symptoms will vary, depending on the specific type of disease a patient has. However, typical symptoms recognized with CVD include: nausea, vomiting, back pain, jaw pain, cold sweats, paleness, dizziness, shortness of breath, lightheadedness, and fainting episodes

(Mayo Clinic, 2018).

Complications. CVD leads to many health complications, including those mentioned in the above section. Because of large amount of plaque accumulation, narrowing of the arteries puts more stress on the heart forcing it to work harder in order to pump adequate oxygen to tissues. Similar to T2DM, if CVD is unaddressed, it could lead to complex heart dysfunctions, improper blood flow, and eventually death

(American Heart Association, 2013).

Prevention. Decades of dietary recommendations have focused on dietary fat and blood cholesterol, and current dietary discussions are often preoccupied with total calories and obesity (Mozzaffarian, 2016). In 1961, the American Heart Association recommended replacing saturated fats with unsaturated fats to prevent CVD. However, in the 1980s and 1990s, these recommendations shifted to an oversimplified low-fat message; reducing all types of fat and replacing them with carbohydrates. These modulations failed to reduce overall risk of for CVD, actually promoting obesity and

T2DM (Wang et al., 2017). Further studies were then needed to investigate actual preventative diets to lower overall CVD risk. The most well-studied dietary patterns associated with lowering CVD risks are the traditional Mediterranean Diet (low in saturated fat and high in vegetable oils), and the Dietary Approaches to Stop

Hypertension or the DASH diet (focusing on macro- and micro-nutrients demonstrated to be effective in reducing risk of HTN) (Davis et al., 2012; Park et al., 2017). Although pathways remain diverse, compared to the conventional low-fat, high carbohydrate

DASH diet, a modified DASH diet higher in vegetable fats (high in mono- and polyunsaturated fats) and lower in carbohydrates (more similar to a Mediterranean diet)

has shown to produce larger cardiometabolic benefits. Both Mediterranean and DASH diet patterns improve a range of risk factors, reduce long-term weight gain, and are consistently associated with lower risk of clinical events (Dietary Guidelines Advisory

Committee, 2015). Researchers confirm the benefits of healthful, food-based diet patterns in two of the largest, longest duration dietary studies ever performed. Of the two studies, one focused on nutrient targets and reducing total fat intake, but results showed no significant effect on CVD or T2DM when compared to the control group. The second study focused on food-based diet patterns and increasing specific healthful foods, especially nuts and extra-virgin olive oil (an estimated increase in mono- and polyunsaturated fat by 4.5%) in Spanish adults with CVD risk factors. Even with smaller dietary changes than in the first study, results of the second study demonstrated a 30% lower risk of developing CVD and T2DM compared to the control group (Mozzaffarian,

2017). Because additives such as sodium and industrial trans fats can be added to or removed from otherwise similar commercially prepared foods (such as processed foods), specific emphasis on their reduction is still warranted. Therefore, based on this evidence, the 2015 Dietary Guidelines Advisory Committee concludes that low-fat diets have no effect reducing CVD risk, and suggests influences on long-term weight gain appear to vary depending on whether high fat foods are consumed together with refined carbohydrates (in which case more weight gain is evident) or in place of refined carbohydrates (in which less weight gain or even relative weight loss is seen).

Treatment. Following a dietary pattern associated with reduced risk of CVD such as a low-moderate carbohydrate intake, increased fruit and vegetable consumption,

increased unsaturated fat intake and decreased saturated fat intake, lessens CVD exposure and promotes a healthier lifestyle. Research on how different risk factors affect the CVD risk profile of can be unclear, and at times, contradictory. However, successful treatments of CVD include glycemic control, management of blood triglycerides and blood pressure (Leon et al., 2015). Thus, the U.S. population should be encouraged and guided to consume dietary patterns associated with reducing CVD and T2DM such as: a diet rich in vegetables, fruit, whole grains, seafood, legumes, and nuts; moderate in low- and non-fat dairy products; lower in red and processed meat; and low in sugar-sweetened foods and beverages and refined grains (Dietary Guidelines Advisory Committee, 2015).

Hypertension

HTN is defined as either a systolic or a diastolic blood pressure measurement consistently higher than an accepted normal value (above 129 or 139 mmHg systolic, and above 89 mmHg diastolic) (Centers for Disease Control and Prevention, 2014). High blood pressure can harden the arteries, which decreases the flow of blood and oxygen to the heart and lead to heart disease (Centers of Disease Control and Prevention, 2016).

Prevalence. According to the CDC, about one in every three US adults, or about

75 million people, have high blood pressure, and only about half of these people have their high blood pressure under control. Recent data reveals that African American women have the highest HTN prevalence at 46.1%. These inconclusive race specific findings using genetic investigational tools, identify candidate genes contributing to the

HTN racial disparity (Musemwa & Gadegbeku, 2017).

Etiology/Causes/Mechanisms. Excessive intake of salt has been identified as the main contributor of high blood pressure. When there’s extra sodium in the bloodstream, it pulls water into the blood vessels, increasing the total volume of blood inside the vessels. With more blood flowing through these vessels, blood pressure begins to rise.

This puts an extra burden on the heart and blood vessels and may lead to or increase overall blood pressure (American Heart Association, 2017). Increased sodium consumption is a common dietary behavior among obese and overweight individuals

(Powell et al., 2012; Goffe et al., 2017). Presently, most of the sodium Americans consume comes from processed and restaurant foods- food items typically containing high amounts of added-fat and added-sugar (Illinois Department of Public Health, 2013).

Canned meats and soups, condiments, pickled foods, traditional snacks (pretzels and crackers) are particularly high in added-salt (Gropper & Smith, 2013). Excessive consumption of these food items has been shown to increase an individual’s risk of becoming overweight or obese. Because salt is so extensively used in food processing and manufacturing, consumption of processed foods (a factor associated with obesity) may account for 75% of total sodium intake (Gropper & Smith, 2013). Although the relationship between obesity and HTN has been established, the mechanism still remains unclear (Jiang et al., 2016). The present review examines the potential mechanisms by which obesity can lead to elevated arterial blood pressure:

1.) Fat contained in the blood circulation can immediately affect certain organs

such as liver and kidney, concomitantly with devastating local actions inside of

the vessels through the formation of atherosclerosis.

2.) Excessive consumption of dietary content high in fat and carbohydrate has

been suggested to acutely stimulate peripheral α1 and β-adrenergic receptors

thereby leading to the elevation of sympathetic activity and HTN.

3.) Obesity causes renal vasodilatation and glomerular hyperfiltration, which act

as a compensatory mechanism to maintain sodium balance. Increased arterial

blood pressure and metabolic abnormalities due to obesity induces inflammation,

oxidative stress, and lipotoxicity, may contribute to the exacerbation of renal

injury or dysfunction (Jiang et al., 2016).

Symptoms. People with high blood pressure usually experience no symptoms unless their blood pressure is extremely high, or they have had high blood pressure for a long time. HTN is commonly known as “the silent killer” because symptoms may go unnoticed. Although uncommonly seen, symptoms patients may experience with HTN include headaches, shortness or breath, and vomiting (Musemwa & Gadegbeku, 2017).

Complications. The excessive pressure on your artery walls caused by high blood pressure can damage blood vessels, as well as organs in the body. The higher the blood pressure and the longer it goes uncontrolled, the greater the damage Uncontrolled high blood pressure can lead to complications including: heart attack, stroke, aneurysm, heart failure, metabolic syndrome, and more (Mayo Clinic, 2018).

Prevention. According to the U.S. Food and Drug Administration (FDA), diets low in sodium may reduce or prevent the risk of high blood pressure. WHO recommends

<2,000 mg of sodium/day for both adults and children. In the U.S., the federal government recommends <1,500 mg/day of sodium for adults who are African-

American, >51 years old, and have HTN. According to U.S. Department of Health and

Human Services, the average intake of individuals > 2 years old is >3400mg/day. One study revealed that obese subjects have a 3.5 fold increased likelihood of having HTN and that 60% of HTN is attributable to increase in adipose stores (Servalle et al., 2017).

Reducing sodium intake is the first line of HTN prevention. For example, one serving of

Heinz Ketchup contains 150mg of sodium/tablespoon, where low-sodium Heinz Ketchup contains 110mg sodium/tablespoon; an overall 40mg reduction per serving. This example provides a quantifiable reduction in dietary modifications that may help reduce total intake of sodium and significantly reduce risk of HTN (Welton et al., 2002).

According to a study, there are other multiple lifestyle modifications for primary prevention of HTN. Current suggestions are as followed:

- Reduce sodium intake to <1000mg per day.

- Maintaining a normal body weight for adults (BMI of 18.5-24.9).

- Reduce sodium intake to <1000mg per day.

- Engage in regular physical activity for at least 30 minutes a day.

- Maintain adequate intake of dietary potassium >3500mg per day.

- Consume a diet rich in vegetables and fruits, and low in dairy products with

reduced content of saturated and total fat (Welton et al., 2002).

Treatment. Treatment of HTN encompasses a range of techniques completely dependent upon the mechanism or etiology of the disease of the patient. Diuretics and calcium channel blockers appear to most prevalent techniques used in HTN treatment

(Musemwa & Gadegbeku, 2017). Diuretics are medicines that help reduce the amount of

water in the body used to treat buildup of excess fluid in the body that occurs with some medical conditions such as HTN Center for Disease Control and Prevention, 2016).

Clinical trials in Black vs Caucasian men demonstrate wide variation in BP responses for both races and an overall, 80–95% overlap in BP responsiveness by drug class (Sehgal,

2004). Another form of HTN treatment involves calcium channel blockers. Calcium blockers help to reduce blood pressure by limiting the amount of calcium or the rate at which calcium flows into the heart muscle and arterial cell walls. Calcium stimulates the heart to contract more forcefully. However, when supply of calcium flow is limited, heart contractions are not as strong which in turn allows blood vessels to relax. This process leads to an overall lower blood pressure (Elliot et al., 2011). Treatment methods vary across race. Current studies acknowledge effectiveness of certain treatments among races and draw general conclusions from this data. For example, African Americans generally respond better to diuretics and calcium channel blockers, where Caucasians have been reported to respond better to other forms of treatments (beta-blockers and angiotensin-converting enzyme inhibitors) (Seghal, 2003). However, studies have shown

“the severity of HTN in most patients requires combination therapy (use of both diuretics and calcium channel blockers) which is considered equally effective across races”

(Musemwa & Gadegbeku, 2017).

Cancer

Cancer is a term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through

the blood and lymph systems causing complications in areas all throughout the body

(National Cancer Institute, 2018).

Prevalence. According to the CDC, cancer is the second leading cause of death in the U.S., exceeded only by CVD. One of every four deaths in the U.S. is due to cancer.

Top cancers based on rates of new cancer cases include breast, prostate, and lung and bronchus cancer. Similarity, top cancers based on rates of cancer deaths include lung and bronchus, female breast, and prostate cancer (Department of Health and Human Services,

Centers for Disease Control and Prevention and National Cancer Institute, 2017).

Evaluations from a five-year duration study conducted in 2015 estimate prevalence among all types of cancer, African American males aged 70-79 had the highest incidence at 8.4%. The same study also estimated prevalence counts of cancer types and found among the top three, Caucasian women had the highest incidence of breast cancer

(844,710 counts), and lung and bronchus (238,563 counts), and Caucasian males had the highest incidence of prostate cancer (736,883 counts).

Etiology/Causes/Mechanisms. Among all of factors, lifestyle behaviors contributing to overweight/obesity make up 40% of all cancers diagnosed (Center for

Disease Control and Prevention, 2017). This includes poor diet such as overconsumption of added-sugar, added-fat, and daily calories, as well as physical inactivity or sedentary behaviors. In combination, these factors promote weight gain and increase risk of obesity. CDC states overweight and obesity is associated with at least thirteen different types of cancer including: Meningioma (cancer of the brain and spinal cord tissue), esophagus, multiple myeloma (cancer of blood cells), thyroid, breast, liver, gallbladder,

upper stomach, pancreas, uterine, kidneys, ovaries, and lastly colon and rectum (Center of Disease Control and Prevention, 2017). Several groups of cancers based on their etiology and pathology have been identified; the four major groups include:

1.) Carcinoma is a cancer that begins in the skin or in tissues that line or cover

internal organs.

2.) Sarcoma is a cancer that begins in bone, cartilage, fat, muscle, blood vessels,

or other connective or supportive tissue.

3.) Leukemia is a cancer that starts in blood-forming tissue, such as the bone

marrow, and causes large numbers of abnormal blood cells to be produced and

enter the blood.

4.) Lymphoma and multiple myeloma are cancers that begin in the cells of the

immune system. Central nervous system cancers are cancers that begin in the

tissues of the brain and spinal cord. Also called malignancy (Center of Disease

Control and Prevention, 2017).

Of those cancer types mentioned, about 55% of all cancers have been diagnosed in women and 24% of those in men (Center for Disease Control and Prevention, 2017).

Several different topics and approaches are connected primarily by their relation to obesity-associated cancers and because of the recent insight they provide for understanding the process” (Berger, 2015). Currently mechanisms between body weight and cancer are complex and are not yet fully understood (American Cancer Society,

2018). Studies do however show potential obesity-related links that promote risk factors associated with all types of cancer such as:

1.) Increased levels and bioavailability of growth factors such as insulin and

insulin-like growth factor (IGF-1).

2.) Increased sex steroid hormones such as estrogen and factors affecting their

metabolism.

3.) Altered adipocytokine levels such as leptin, adiponectin, and visfatin, all

originally thought to primarily affect energy balance, but now known to have

growth, immune, and tumor-regulatory functions.

4.) Low-grade inflammation and oxidative stress affecting growth-promoting

cytokines and immune modulation, and more recently.

5.) Altered microbiomes, especially those composing the intestinal flora (Berger,

2015; American Cancer Society, 2018).

Understanding mechanisms linking obesity and cancer progression in cancer types has great importance for a large proportion of cancer survivors and will likely also benefit survivors of other obesity-associated cancer types (Allot & Hursting, 2016).

Symptoms. Cancer is a group of diseases that can cause almost any sign or symptom. The signs and symptoms will depend on where the cancer is, how big it is, and how much it affects the organs or tissues. If a cancer has spread (metastasized), signs or symptoms may appear in different parts of the body (National Cancer Institute, 2015). A few identified symptoms include: fatigue, decreased immunity, nausea and vomiting, excessive sleeping, fever, weight loss and more.

Complications. According to the National Cancer Institute, any form of cancer when left untreated has the potential (depending on the type and stage) to break through

the dimensions of its organ of origin and invade the other parts of the body. This form of the disease proves fatal and is termed as metastatic cancer.

Prevention. The CDC has administered preventative cancer plans across the entire U.S. to help reduce overall risk of the disease. Preventative measures vary across states due to differences in race and environment. Most however, focus on environmental factors, lifestyle behaviors, vaccines, and genetic variations (Ohio Partners for Cancer Control, 2015). A brief overview of how to reduce risk factors of developing cancers are as follows: Environmental factors such as smoking, and exposure to secondhand smoke, and radon gas increases a person’s risk for all cancers especially lung cancer. Avoid UV light (sunlight, tanning beds, tanning lamps etc.) for these increase risks of skin cancer. Healthy lifestyle behaviors such as daily physical activity, following a healthy diet, and maintaining a healthy weight reduce cancer risk (normal BMI of 18.5-

24.9). Vaccines may also help prevent certain cancers. Obtaining a human papillomavirus vaccination (HPV), one of the most common sexually transmitted infectious diseases has been shown to increase risks of cervical cancer. Lastly, genetic variations and polymorphisms can play a major role in cancer development. Knowledge gained from family history and genetic testing can play a role in cancer prevention and early detection. A detailed family history can help identify an inherited predisposition for cancer and can guide people to an appropriate referral for genetic counseling and testing”

(Center of Disease Control and Prevention, 2018).

Treatment. There are numerous types of cancer treatments that differ based on the type of cancer and stages of progression (National Cancer Institute, 2015). The most

common forms of treatments are as follows: Surgery works best for solid tumors that are contained in one area. It is a local treatment, meaning that it treats only the part of your body with the cancer. It is not used for leukemia (a type of blood cancer) or for cancers that have spread. Depending on the type of cancer, and how advanced it is, surgery can remove an entire tumor, debulk a tumor, or remove tumors causing pressure or discomfort. Another type of treatment, radiation therapy, at high doses, kills cancer cells or slows their growth by damaging their DNA. Cancer cells whose DNA is damaged beyond repair stop dividing or die. When the damaged cells die, they are broken down and removed by the body. Radiation therapy depends on the type, cancer, size, and location of the cancer, as well as current and past medical conditions. Among one of the most common, chemotherapy is another type of cancer treatment that uses drugs to kill cancer cells; stopping or slowing the growth of cancer cells, which grow and divide quickly. Immunotherapy is another type of biological therapy that uses substances made from living organisms to treat cancer. These treatments can either help the immune system attack the cancer directly or stimulate the immune system in a more general way.

Examples of these are checkpoint inhibitors and adoptive cancer transfers, monclonal antibodies, and treatment vaccines. Lastly, hormone therapy may be utilized to help slow or stop the growth of cancer that uses hormones to grow. Hormone therapy can lessen the chance that cancer will return or stop or slow its growth or ease cancer symptoms.

Two types include those that block the body’s ability to produce hormones, and those that interfere with how hormones behave in the body (National Cancer Institute, 2015; Center for Disease Control and Prevention, 2018).

Other Health Outcomes Related to Overweight and Obesity

Obesity is also linked to several other diseases other than chronic diseases.

Several recent studies have contributed to evidence of an association between obesity and the development of Rheumatoid Arthritis (RA) as well as Osteoarthritis (OA) (George &

Baker, 2016). In addition, it has been suggested that both depression and obesity are disorders of stress with dysregulation of the stress system, confirming an association between depression and obesity (Jantaratnotai et al., 2016). Lastly, obesity has shown to increase risks associated with gastrointestinal complications (Camilleri et al., 2017).

Rheumatoid Arthritis

RA can be defined as an autoimmune disease in which the body’s immune system

– which normally protects its health by attacking foreign substances like bacteria and viruses – mistakenly attacks the joints. This creates inflammation that causes the tissue that lines the inside of joints to thicken, resulting in swelling and pain in and around the joints (Arthritis Foundation, 2018).

Prevalence. The CDC estimate the average annual arthritis prevalence in US adults 18 years or older. Overall, an estimated 22.7% (54.4 million) of adults had doctor- diagnosed arthritis, with significantly higher age-adjusted prevalence in women (23.5%) than in men (18.1%). Findings show age-adjusted prevalence of arthritis among adults reporting no leisure time physical activity (23.6%) is significantly higher than the prevalence of arthritis among adults who report meeting physical activity recommendations (18.1%). In addition, arthritis prevalence shows to increase with age.

Etiology/Causes/Mechanisms. RA occurs when your immune system attacks the synovium, or the lining of the membranes that surround the joints. The resulting inflammation thickens the synovium, which can eventually destroy the cartilage and bone within the joint. In addition, the tendons and ligaments that hold the joint together weaken and stretch, where gradually, the joint loses its shape and alignment (Mayo

Clinic, 2018). The obesity epidemic has impacted practically every area of health, including the care of patients with RA (George & Baker, 2016). Potential biologic mechanisms are currently observed in order to explain an association between obesity and RA, but are yet to be determined. It is possible that the mechanism through which obesity contributes to RA development is specific to a distinct pathophysiology. Another potential explanation of this phenomenon is differential misclassification of RA. Because obesity is also associated with OA, disability, and chronic pain, patients with obesity may be more likely to be misclassified (George & Baker, 2016). Studies show a close association of obesity with activation of pro-inflammatory pathways, narrowing joint- space in the knees, and reduced functional capacity. These factors suggest obese RA patients may have more active and severe disease, and a worse quality of life (Kalinoglou et al., 2011). One study analyzed being obese at the onset of RA reduces the odds of achieving remission by 43% and the odds of achieving sustained remission by 51% (Liu et al., 2016).

Contrasting View. In contrast, studies in patients with early RA surprisingly suggest that obesity (as assessed by the BMI) may protect against joint damage (Giles et al., 2009). One study utilized Radiographic Scoring (RS), a method used to measure and

estimate the RA progression. Results showed patients of normal weight had significantly more joint damage at study entry than obese patients (mean RS 4.5 versus 2.4; 0.004) and experienced significantly more progression than obese patients (RS 3.4 versus 1.3; P

0.011). At 3 years, their RS score was twice as high as that of the obese patients (7.5 versus 3.7; P < 0.001) (Westhoff et al., 2007). In addition, weight loss that occurs in the setting of inflammatory diseases such as RA may also be lead to a disease called cachectic obesity, or low lean muscle mass with high body fat percentage. This disease is associated with muscle atrophy, fatigue, weakness and significant loss of appetite

(Westhoff et al, 2007). Therefore, much discussion has ensued about how to best define

“obesity” in RA and other inflammatory conditions where BMI may not adequately reflect the extent of adiposity (George & Baker, 2016). Therefore, clinicians should be aware that many RA patients with a relatively normal BMI might have substantial adiposity that may still put them at risk for comorbidities traditionally associated with obesity (George & Baker, 2016).

Symptoms. Signs and symptoms of RA may include: tender, warm, swollen joints, joint stiffness that is usually worse in the mornings and after inactivity, fatigue, fever and weight loss (Mayo Clinic, 2018).

Complications. Early stages of RA tends to affect your smaller joints first- particularly the joints that attach your fingers to your hands and your toes to your feet.

However, as the disease progresses, symptoms often spread to the wrists, knees, ankles, elbows, hips and shoulders. In most cases, symptoms occur in the same joints on both sides of your body (Mayo Clinic, 2018). Also, according to the CDC, progression of RA

could reduce a person’s physical abilities- limiting them to certain tasks. These limitations negatively impact quality of life.

Prevention. Unfortunately because the mechanisms of RA are not fully understood, prevention methods remain generally vague. According to the CDC, maintaining a healthy weight, staying physical active, avoiding smoking, and breastfeeding, are all factors identified to decrease risks associated with RA (Center for

Disease Control and Prevention, 2017).

Treatment. The CDC’s Arthritis Program promotes key methods in order to help individuals affected by arthritis be in control of their condition, and their lives. They include staying active, watching weight status, frequent doctor visits, and occupational therapy. In addition, some medications may be required to slow disease progression and prevent joint deformity- these are called disease-modifying antirheumatic drugs

(DMARDs); or biological response modifiers (biologicals) are medications that are an effective second-line treatment(Mayo Clinic, 2018).

Osteoarthritis

OA is the clinical syndrome of joint pain accompanied by varying degrees of functional limitation and reduced quality of life. Pathologically, it is characterized by localized loss of cartilage, remodeling of adjacent bone, and associated inflammation

(National Institute of Health and Care Excellence, 2014).

Etiology/Causes/Mechanisms. Obesity is widely acknowledged as a risk factor for both the incidence and progression of OA, and has a negative influence on outcomes

(Bliddal et al., 2014). Studies show body weight influences the severity of OA; obese

individuals have significantly more severe joint degeneration in the knees compared with normal weight or underweight individual (Lementowski, 2008). Another study found with every 5 kg of weight gain, there is a 36% increase in the risk of knee OA (Mehleman et al., 2010). One major reason for this is that weight gain increases joint load (Bliddal et al., 2014). For example, a study of overweight and obese older adults with knee OA estimated that every pound of weight lost resulted in a fourfold reduction in the load exerted on the knee per step during daily activities, which appears to be clinically meaningful (Messier et al., 2005).

Symptoms. Common symptoms of OA include: pain or aching, stiffness, decreased range of motion (or flexibility), and swelling (Center for Disease Control and

Prevention, 2017).

Complications. OA can cause severe joint pain, swelling, and stiffness. In some cases, it also causes reduced function and disability; some people are no longer able to do daily tasks or work. Severe cases may require joint replacement surgery, particularly for knee or hip OA (Center for Disease Control and Prevention, 2017).

Prevention. According to the CDC, prevention of OA may include: maintaining a healthy weight, controlling blood sugar levels, staying physically active, protecting joints by avoiding low impact activities.

Treatment. OA experts recommend weight loss as well as exercise in the treatment and management of overweight or obese patients with OA (Bliddal et al.,

2014). “Exercise has been shown to strengthen muscles that support the joints, reduce pain and improve physical function” (Messier et al., 2005). However, combined exercise

and diet therapy compared with either exercise or diet alone, shows greater improvements in gait, knee pain and physical function (Messier et al., 2005).

Depression

Depression is a common, but serious mood disorder. Depression is when a sad mood lasts for a long time and interferes with normal, everyday functioning such as how you feel, think, and handle daily activities, such as sleeping, eating, or working (Center for Disease Control and Prevention, 2018; National Institute of Mental Health, 2018).

Prevalence. The prevalence of depression, and associated risk of poor health outcomes, is elevated in the obese population. According to the CDC, in 2013–2016,

8.1% of American adults aged 20 and over had depression in a given two-week period where women (10.4%) were almost twice as likely as were men (5.5%) to have had depression. About 80% of adults with depression reported at least some difficulty with work, home, or social activities because of their depression symptoms (Center for

Disease Control Prevention, 2018).

Etiology/Causes/Mechanisms of How Depression May Cause Obesity. The exact cause of depression is unknown. Causes of depression vary from person to person, however common factors associated with an increased risk of developing depression include: personal or family history of depression, major life changes, trauma, or stress, chronic disease (such as obesity), certain physical illnesses and medications (National

Institute of Mental Health, 2018; Center for Disease Control and Prevention, 2018).

Among these factors, depressive symptoms are often associated with obesity, and emotional eating may play a considerable role in weight gain (Lazarevich et al., 2016).

Although the precise mechanism that causes depression remains unclear, textbook causes known thus far address social isolation in combination with depression. “In depression with atypical features, individuals are prone to developing abnormal eating behaviors such as emotional eating, or overeating in response to negative emotions. These patterns include eating to cope with stress, anxiety, frustration, sadness and anger, among others, and are often related to difficulty in controlling the quantity of one's food intake” (Ozier et al., 2008). A study using the Beck Depression Inventory (BDI), a 4 point-scale that measures the severity of depressive symptomatology, showed within a sample of 47 overweight and 102 obese subjects; BMI correlated significantly with high BDI scores (r

= 0.23, P < 0.01). Symptomatic participants were more concerned about their shape, had lower self-esteem (P-values < 0.03), and tended to be more concerned about their weight and eating (P values < 0.11) than non-depressed participants (Werrij et al., 2005). One study found “in overweight or obese college students, almost 30% engaged in at least one unhealthy weight loss practice and found an association between depressive symptoms and engagement in unhealthy weight loss practices” (Davila et al., 2014). A possible explanation for these findings suggests that depressed individuals use unhealthy weight loss practices as a way to cope with problems, elevate mood, and regulate emotional distress or negative affect. At higher BMIs (e.g., overweight or obese), depression may be the driving force prompting both college women and college men to engage in unhealthy weight loss practices to lose weight (Polivy & Herman, 2002, 1995).

Therefore, obesity interventions targeting college students should provide education on healthy weight loss practices and the dangers of unhealthy weight loss practices, screen

for depression, and include supportive strategies (e.g., counseling referrals, coping techniques) for those screening high for depression symptoms (Davila et al., 2014).

These results highlight the likely bidirectional relationship between obesity and depression (Preiss et al., 2013)

Etiology/Causes/Mechanisms of How Obesity May Cause Depression.

Previous studies have also confirmed that overweight/obesity may in fact cause depression. A study of self-rated measures of somatic well-being were significantly lower among obese patients (BMI ≥ 30) when compared to non-obese patients

(Jantaratnotai et al., 2016). Data conducted in 2005-2010 revealed 34.6% of U.S. adults aged twenty and over were obese and 7.2% had depression, based on depressive symptoms (Center for Disease Control and Prevention, 2013). Body dissatisfaction is identified as a reliable predictor of depression. BMI is the most common factor linked to body dissatisfaction, increased depression, and lower self-esteem among college students

(Nemiary et al., 2013). One study showed that in a survey of 1,490 youth in grades seven through twelve, obese youth reported higher body dissatisfaction and greater depressive symptoms, including anhedonia and negative self-esteem compared to normal weight youth (Goldfield et al., 2010). These studies suggest obesity may directly or indirectly cause depression in populations as early as adolescents.

Symptoms. As stated in the definition, depressive symptoms vary from person to person and involve a wide range of concerns. These include: Feeling sad or anxious often or all the time, not wanting to do activities that used to be fun, feeling irritable‚ easily frustrated‚ or restless, having trouble falling asleep or staying asleep, waking up

too early or sleeping too much, eating more or less than usual or having no appetite, experiencing aches, pains, headaches, or stomach problems that do not improve with treatment, having trouble concentrating, remembering details, or making decisions, feeling tired‚ even after sleeping well, feeling guilty, worthless, or helpless and or thinking about suicide or hurting oneself.

Complications. Depression is a serious disorder that can take a terrible toll on one’s life as well as their friends and family. Depression often gets worse if it isn't treated, resulting in emotional, behavioral and health problems that affect every area of your life. Complications associated with depression could include: excess weight or obesity, which can lead to heart disease and diabetes, pain or physical illness, alcohol or drug misuse, anxiety, panic disorder or social phobia, family conflicts, relationship difficulties, and work or school problems, social isolation, suicidal feelings, suicide attempts or suicide (Mayo Clinic, 2018).

Prevention. Prevention of depression is unclear, however there are strategies in place that may help- these include, taking steps to address and cope with stress, building self-esteem, and establishing strong and open relationships with family and friends

(Mayo Clinic, 2018).

Treatment. Treatment for depression can help reduce symptoms and shorten how long the depression lasts. According to the CDC, treatment can include getting therapy and/or taking medications. Many people benefit from psychotherapy—also called therapy or counseling. Most therapy lasts for a short time and focuses on thoughts‚ feelings‚ and current life issues. In some cases‚ understanding past experiences can help‚

but finding ways to address what is happening now can help with coping and prepare patients for challenges in their future. With therapy, patients work with a therapist to learn skills identified to help cope with life, change behaviors that are causing problems‚ and find solutions. Some of these therapeutic measures address healthier lifestyle behaviors (diet and physical activity), stress coping techniques, and better development of relationships with family and friends, and more.

Gastrointestinal Complications

GI complications include an array of diseases and disorders such as gastroesophageal reflux disease (GERD) erosive esophagitis, Barrett’s esophagus, esophageal adenocarcinoma, erosive gastritis, gastric cancer, diarrhea, colonic diverticular disease, polyps, cancer, liver disease including nonalcoholic fatty liver disease, cirrhosis, hepatocellular carcinoma, gallstones, acute pancreatitis, and pancreatic cancer.

Prevalence. Research indicates that the prevalence of GI complications caused by obesity and DM has been increasing, with up to 75% of diabetic patients experiencing GI symptoms (Mayo Clinic, 2018).

Etiology/Causes/Mechanisms. Obesity is the direct cause or is a significant risk factor for multiple GI complications (Black & Gupta 2018). When obesity is a risk factor, it may interact with other pathogenetic mechanisms and result in earlier presentation of disease or more complicated disease (Camilleri et al., 2017). Although mechanisms for each disease remain complex, obesity has been shown to increase the risk of esophageal motility disorders. For example, esophageal transit time can be

prolonged significantly in subjects with obesity compared with lean subjects, possibly because of increased gastric and gastroesophageal junction resistance (Camilleri et al.,

2017). Excess body weight has also been shown to increase abdominal girth producing higher intra-abdominal pressures and reducing LES (pressures are greater in the posterior and left lateral positions and lower in the anterior and right lateral positions) pressure. In addition, obesity is the primary risk factor for developing erosive esophagitis (or inflammation of the esophagus), and may interfere with adipose tissue regulation, adequate immune response, and adipokine secretion (Camilleri et al., 2017). Inability to control GI inflammation or other issues is associated with severe long-term GI complications (Black & Gupta, 2018).

Symptoms. Symptoms vary and depend on the type and progression of the GI disease. Symptoms may include: nausea, vomiting, diarrhea, constipation, dysphagia, heartburn (GERD), chest pain, abdominal pain, and gastritis (Camilleri et al., 2017).

Complications. GI complications and symptoms may consequently affect the ability to perform day to day tasks such as walking, eating, drinking, etc. If complications are unaddressed, severe complications such as internal bleeding, sepsis, cancer, and permanent bowl damage may develop (Black & Gupta, 2018; Margina et al.,

2015).

Prevention. Lifestyle changes and control of metabolic risk factors may prevent the development of numerous GI complications and diseases. Physical activity and dietary changes reducing fatty acid intake have been reported to have a preventive effect

on the development of obesity, and furthermore GI complications or diseases (Margina et al, 2015).

Treatment. Treatment of GI complications vary drastically depending on the type and progression of the disease. Dietary and lifestyle changes reducing obesity risk such as excess adipose tissue may decrease chance of developing GI complications (Black &

Gupta, 2018). In addition, various medications may be administered regimen in attempt to resolve symptoms. Potential modifications include discontinuing aggravating medications, reducing the dose of a medication, switching to the modified release preparation of metformin, or switching agents within a class, particularly for the GLP-1 agonists. If a patient's symptoms persist despite changes to their therapeutic regimens, endoscopy, stool culture, and computed tomography can be used to exclude other possible causes of symptoms (Margina et al., 2015; Camilleri et al., 2017).

American Dietary Recommendations for Prevention of Chronic Disease

A growing body of research has examined the relationship between overall eating patterns, health, and risk of chronic disease, and findings on these relationships are sufficiently well established to support dietary guidance (The 2015-2020 Dietary

Guidelines, 2015). These guidelines focus on the big picture with recommendations to help Americans make choices that promote health and help to reduce the risk of chronic disease. Guidelines aim to deliver these recommendations for each food group such as grains, dairy, fruit, vegetable, protein, and dietary fat through the visual MyPlate tool.

MyPlate uses current dietary recommendations (such as the 2015-2020 dietary guidelines) to represent what the ideal meal should contain/look like. According to these

recommendations, the percent of calories from carbohydrate sources should range from

45%-65% of total calories per day, calories from protein sources should range between

10%-35% of total calories per day, and calories from fat sources should range between

20%-35% of total calories per day (saturated fat is limited to <10% of total daily calories per day). Although dietary recommendations are available for all to follow and use, studies show most individuals are not adhering to these recommendations, consuming more calories per day than recommended, and consuming majority of their calories from carbohydrate and fat sources (Meldrum et al., 2017; Davey et al., 2017). Factors contributing to obesity are discussed in previous sections. In order to ensure college students understand dietary intake recommendations, education addressing the importance of each food group may help guide students in making appropriate dietary choices.

Grains

Grains fall under the carbohydrate section in MyPlate and include any food made from wheat, rice, oats, cornmeal, barley or another cereal grain. It is important to note, however, there are two types of grains, whole grains and refined grains (United States

Department of Agriculture, 2017). Healthy eating patterns include whole grains and limit the intake of refined grains and products made with refined grains. Whole grains contain the entire kernel, including the endosperm, bran, and germ which contains dietary fiber, iron, zinc, manganese, folate, magnesium, copper, thiamin, niacin, vitamin B6, phosphorus, selenium, riboflavin, and vitamin A. Refined grains, as previously mentioned, have been processed to remove the bran and germ, which removes dietary

fiber, iron, and other nutrients. Consuming adequate amounts of whole grains ensures appropriate intake of such essential nutrients thereby decreasing the risk of various nutrient deficiencies. The recommended amount of grains in at the 2,000-calorie diet for young adults is six ounce-equivalents per day for females and 8-ounce-equivalents for males, where at least half of this amount is from whole grains. The most direct way to meet the whole grain recommendation is to choose 100 percent whole-grain foods for at least half of all grains consumed. A quick tip when identifying whole grain items,

“whole-grain” should be the first or second ingredient, after water on the label. Examples of whole-grain food items include: oatmeal, quinoa and brown rice. By simply reducing refined grain consumption and increasing whole grain consumption, individuals can meet daily recommendations for not only whole-grains, but various nutrients as well (2015-

2020 Dietary Guidelines for Americans, 2015)

Vegetables, Legumes, & Fruit

Vegetables, legumes (also in protein section of MyPlate), and fruit also fall under the carbohydrate section in MyPlate. Healthy eating patterns include a variety of vegetables from all of the five vegetable subgroups—dark green, red and orange, legumes

(beans and peas), starchy, and other (The 2015-2020 Dietary Guidelines, 2015).

Vegetables are important sources of many nutrients, including dietary fiber, potassium, vitamin A, vitamin C, vitamin K, copper, magnesium, vitamin E, vitamin B6, folate, iron, manganese, thiamin, niacin, and choline. Each of the vegetable subgroups contributes different combinations of nutrients, making it important for individuals to consume vegetables from all the subgroups. Within the vegetable subgroups, legumes are an

excellent source of dietary fiber and other nutrients such as potassium and folate.

Examples of legumes include: kidney beans, pinto beans, white beans, black beans, garbanzo beans (chickpeas), lima beans (mature, dried), split peas, lentils, and edamame

(green soybeans). Legumes are also great sources of protein as well, and therefore may be considered either a vegetable or protein source. The recommended amount of vegetables for a 2,000-calorie diet is 2½ cup-equivalents of vegetables per day. In addition, weekly amounts from each vegetable subgroup are recommended to ensure variety and meet nutrient needs (2015-2020 Dietary Guidelines for Americans, 2015).

Healthy eating patterns include fruits, especially whole fruits. Among the many nutrient’s fruits provide are dietary fiber, potassium, and vitamin C (The 2015-2020

Dietary Guidelines, 2015). The fruits food group includes whole fruits and 100% fruit juice; however, recommendations focus on solely on consumption of whole fruits.

Although fruit juice can be part of healthy eating patterns, it is lower than whole fruit in dietary fiber and when consumed in excess can contribute extra calories. The recommended amount of fruits for young male and female adults based on a 2,000- calorie diet is 2 cup-equivalents per day, where at least half of the recommended amount of fruits should come from whole fruits (The 2015-2020 Dietary Guidelines, 2015).

Dairy

Dairy products all under all sections of MyPlate. Healthy eating patterns include fat-free and low-fat (1%) dairy, including milk, yogurt, cheese, or fortified soy beverages

(commonly known as “soymilk”) (The 2015-2020 Dietary Guidelines, 2015). Soy beverages fortified with calcium, vitamin A, and vitamin D, are included as part of the

dairy group because they are similar to milk based on nutrient composition and in their use in meals. The dairy group contributes many nutrients, including calcium, phosphorus, vitamin A, vitamin D (in products fortified with vitamin D), riboflavin, vitamin B12, protein, potassium, zinc, choline, magnesium, and selenium. Other products sold as “milks” but made from plants (e.g., almond, rice, coconut, and hemp

“milks”) may contain calcium and be consumed as a source of calcium, but they are not included as part of the dairy group because their overall nutritional content is not similar to dairy milk and fortified soy beverages (soymilk). Dairy recommendations for young adults based on a 2,000-calorie diet are approximately 3 cup-equivalents per day (The

2015-2020 Dietary Guidelines, 2015).

Protein

Healthy eating patterns include a variety of protein foods in nutrient-dense forms.

The protein foods group comprises a broad group of foods from both animal and plant sources and includes several subgroups: seafood; meats, poultry, and eggs; and nuts, seeds, and soy products (The 2015-2020 Dietary Guidelines, 2015). Legumes (as previously mentioned) may also be considered part of the protein foods group. Selecting a variety of protein foods helps to improve nutrient intake and health benefits. Protein foods are important sources of nutrients in addition to protein, including B vitamins (e.g., niacin, vitamin B12, vitamin B6 , and riboflavin), selenium, choline, phosphorus, zinc, copper, vitamin D, and vitamin E). Nutrients provided by various types of protein foods differ. For example, meats provide the most zinc, seafood provides the most vitamin B12 and vitamin D, while poultry provides the most niacin. Therefore, depending on the

individuals needs, one may consume one source more than the other. Daily protein recommendations for young adult females is approximately 5 ½ ounce-equivalents and 6

½ ounce-equivalents for males (The 2015-2020 Dietary Guidelines, 2015).

Fat/Oils

Oils are fats that contain a high percentage of monounsaturated and polyunsaturated fats and are liquid at room temperature. Although they are not a food group, oils are emphasized as part of healthy eating patterns because they are the major source of essential fatty acids and vitamin E (The 2015-2020 Dietary Guidelines, 2015).

Oils are also the most concentrated source of calories where the amount consumed should fall within the recommended daily intake for total fats without exceeding calorie limits.

In addition, oils should replace solid fats rather than being added to the diet. Most oils are high in monounsaturated or polyunsaturated fats, and low in saturated fats, while solid fats are solid at room temperature, and typically contain higher amounts of saturated fat. Oils from plant sources (vegetable and nut oils) do not contain any cholesterol. In fact, no plant foods contain cholesterol. Commonly consumed oils extracted from plants include canola, corn, olive, peanut, safflower, soybean, and sunflower oils. Oils also are naturally present in nuts, seeds, seafood, olives, and avocados. Solid fats, however, come from many animal foods and can be made from vegetable oils through a process called hydrogenation. Some common fats are: butter, milk fat, beef fat (tallow, suet), chicken fat, pork fat (lard), stick margarine, shortening, and partially hydrogenated oil. Oil recommendations for young adult females is approximately six teaspoons per day and seven teaspoons per day for males (The 2015-2020 Dietary Guidelines, 2015).

Weight Management

Obesity is a major public health concern, and effective population-wide intervention strategies aimed at reducing obesity are needed (Nelson et al.,2008). The

Academy of Nutrition and Dietetics recognizes the obesity epidemic, recommending weight loss and weight maintenance therapy through a comprehensive weight management program including diet, physical activity, and behavior therapy. It is important to note, the weight management intervention decided ultimately depends on the goals of the individual. Weight loss refers to a reduction of the total body mass.

Although weight loss in obese and overweight individuals is an encouraged part of the weight management plan, reduction of total pounds on a scale may not be the appropriate focus (The American Council of Exercise, 2009; Volek & Phinney, 2012). However, education on fat-loss and increased fat-free mass, instead of overall weight-loss, can play a significant role in how a person perceives their weight change successes (Volek &

Phinney, 2012). Body composition, or a measure or lean muscle tissue vs. fat tissue, is a significant predictor of overall health status and or predictor of chronic disease development (Srivastava et al., 2014). Therefore, encouraging fat loss instead of weight loss may be recognized as a useful weight management tool. The American Council on

Exercise (ACE) general body-fat percentages for different classifications can be found in table 1.

Table 1.

General Body-Fat Percentage Categories

Classification Women (% Fat) Men (% Fat)

Essential Fat 10-13 2-5

Athletes 14-20 6-13

Fitness 21-24 14-17

Average 25-31 18-24

Obese 32 or higher 25 or higher (The American Council of Exercise, 2009).

Components of Successful Weight Management

According to the Academy of Nutrition and Dietetics, the most successful weight

management plans combine diet, exercise and behavioral therapy. One pound of fat is

equivalent to 3,500 kcals. Therefore, in order to lose a healthy amount of weight per

week (approximately 1-2 pounds), a reduction in energy of 500 to 1,000 kcal/day is

required. This reduction can come solely from calorie restriction; however, research

shows if weight loss excludes exercise (resistance training in particular) approximately

25% of every pound lost will come from lean, calorie-burning muscle (Muth, 2009).

Promoting lean muscle tissue growth through both diet and exercise facilitates greater

weight loss or more importantly, fat loss (Volek & Phinney, 2012). Another study

examined the impact of diet and increasing exercise on health improvements among a

diet group only, exercise group only, and combined therapy group. Health improvements

included: weight loss, easier breathing, less stressed, better sleep, increased mobility, less

joint pain/discomfort, less back pain, less depressed/anxious, lower blood pressure,

improved blood sugar levels, lower cholesterol, better balance, fewer illnesses, less medication, smoking less. Results showed patients in the diet group were more likely to improve three of the 15 possible health problems listed, and the exercise group improved six of 15, but the exercise and diet group was more likely to improve eleven of 15 health problems compared to the control group (Elliot & Hamlin, 2018). Lastly, behavior modulations play a key role in long-term weight loss and weight management. One study examined the effects of a behavioral weight loss treatment that emphasized physical activity, meditation, and moderated-meditation models in the self-efficacy-self-regulation among women struggling with weight management. Results found participants were less likely to engage in emotional eating and had higher intake of fruits and vegetables after the intervention. Findings clariﬁed relationships of self-efﬁcacy, self-regulation, and mood for improving weight loss behaviors within a behavioral treatment (Annesi et al.,

2017).

Weight Management Methods

Currently there are many weight management methods utilized. Examples of these methods include those mentioned above- exercise, diet-therapy and behavioral- therapy - along with these are tailored prescription diets recommended by a registered dietitian or physician, FD, surgery, and prescription medications. Although exercise, diet-therapy and behavioral-therapy are favorable methods of treating overweight/obese patients among health care professionals, in more extreme conditions, individuals may turn to FD, surgery, and or medications for weight loss (Bacon & Aphramor, 2011;

Anderson et al., 200; Summa Health, 2018).

Prescription Diets. Prescription diets are often recommended to overweight/obese patients by a registered dietitian or physician for weight management

(The Academy of Nutrition and Dietetics, 2017). According to a study, official dietary recommendations and guidelines given to patients by a health care professional had higher adherence rates long term vs. commercial or self-imposed dietary restriction diets (Julia et al. 2014). Prescription diets are developed and tailored to a specific patient’s wants, preferences, and necessary dietary need (The Academy of Nutrition and Dietetics, 2017). Examples of standardized weight management methods include:

The Diabetic Diet (low- to moderate-carbohydrate diet), The Heart Healthy Diet (low- to moderate- fat diet with low consumption of saturated fats), or MAD (low- carbohydrate, high protein and fat diet), and more (The Acadamey of Nutrition and

Dietetics, 2019).

Extreme Dieting/Fad Diets. Although weight management plans including behavior modifications, visualizations, diet follow-ups, and exercise programs are critical components of successful, weight loss diet programs, short-term weight loss methods such as FD are sometimes preferred among overweight and or obese populations

(Academy of Nutrition and Dietetics, 2018; Anderson et al., 2001; Crosser, 1985).

Individuals who adhere to extreme short-term weight loss diets utilize these in hopes of achieving quick weight loss, however, most of these interventions are typically unsustainable for most participants, resulting in reversed dietary behaviors, and weight gain (Bacon & Aphramor, 2011; Anderson et al., 2001; Crosser, 1985). Short-term weight loss methods identified decades ago and that are currently still in use include:

fasting, low-fat low-protein high-carbohydrate diets (Pritikin Diet), high-fiber, low- carbohydrate, unsaturated fats, and lean protein (South Beach Diet), low-carbohydrate moderate-protein high-fat diets (KD and MAD), liquid protein-sparing modified fast diets

(Cambridge & “Last Chance” Diets), one or two food diets (Fiber or Fruit Diet), magic ingredient diets (Grapefruit or Magic Mayo Diet) and more (Crosser, 1985). The list of

FD continues to expand, and with the expansion comes an increased need for nutrition education prior to intervention implication.

Surgery. When a person’s BMI reaches the point of severe obesity, surgical weight loss becomes an option. When the BMI gets this high, the excess weight places a great deal of strain on a person’s body, and the likelihood of successfully losing weight and keeping it off with nonsurgical methods decreases significantly (Summa Health,

2018). One well-known and successful surgical weight loss procedure is gastric bypass.

This minimally invasive procedure creates a small stomach “pouch” with staples and separating it from the rest of the stomach. A portion of the small intestine is then

“bypassed” and re-attached to the stomach in a different way where the remainder of the stomach continues to produce digestive enzymes. As a result, patients eat less food and absorb only part of the food they consume. This procedure creates a feeling of fullness sooner after eating and allows for absorption of only part of the food eaten (Summa

Health, 2018).

Medication. In addition to surgery, prescription medications in combination with changes to behavior, including eating and physical activity habits, may help some people lose weight. On average, people who take prescription medications as part of a lifestyle

program lose between 3%-9% more of their starting body weight than people in a lifestyle program who do not take medication (National Institute of Diabetes and

Digestive and Kidney Diseases, 2016). Medications may help patients feel less hungry or full sooner or decrease the body’s overall ability to absorb fat from dietary sources, thus contributing to an increased weight loss. Examples of prescription medications approved by the FDA for overweight and obesity treatment include: Orlistat, Lorcaserin,

Phentermine-topiramate, Naltrexone-bupropion, Liraglutide, Phentermine,

Benzphetamine, Diethylpropion, and Phendimetrazine. Each medication is approved for a specific population and provides a brief overview of how the drug works, any potential side effects, and warnings.

Obesity in College Student Population

Recent statistics indicate that over one-third of college students are currently overweight or obese, however, the underlying factors contributing to excessive weight gain are still not fully understood (Odlaug et al., 2015).

Prevalence of Obesity Among College Students

According to the CDC, the prevalence of obesity is 35.7% among young adults aged 20 to 39 years – doubling the prevalence of obesity in young adults in the last 30 years (Nelson et al., 2008). Recent data shows approximately 41% of the population aged between 17-24 is enrolled in college (Kena et al., 2014). The phenomenon of weight gain in college attendees has been studied since the 1980s and currently is still being investigated. Attention has been drawn to weight gain in the freshman year and more recently has focused on the persistence of weight gain beyond the freshman year

and subsequent changes in the body’s adipose composition (Fedewa e tal., 2014).

College students have become more aware of these weight gain trends and are looking for ways to overcome struggles associated with weight gain (Swanson, 2015).

Factors Contributing to Obesity in College Students

Although lifestyle modifications involving diet, exercise, and other behavior changes are identified as successful tools in weight management, majority of individuals are unable to maintain a healthy weight long-term (Bacon & Aphramor, 2011). Long- term success rates of weight management are low. Study results show individuals who participate in structured weight management programs designed to facilitate health weight loss in the U.S. regain 33% to 100% of the lost weight within a five-year period

(Bacon & Aphramor, 2011; Anderson et al., 2001). College students in particular incur multiple challenges in weight management. In this specific population, factors contributing to obesity include stress, lack of time, poor dietary choices, and lack of knowledge (Greaney et al., 2009).

Newly Found Independence. Emerging adulthood is a time for the exploration of new ideologies and behaviors which allow individuals to express one's’ own thoughts and beliefs (Nelson et al., 2008). As young adults leave their parental home and explore new environments, new behaviors are adopted or shaped (Swanson, 2015). In American middle-class environments, college is not only an expected part of the life plan; it is the ultimate symbol of independence. When transitioning from one’s home to the university, students are led to believe that they will finally be able to separate and distinguish themselves from their parents and to realize their individual potential—to find

themselves, to develop their voices, to follow their passions, and to influence the world

(Stephens et al., 2012). One defining characteristic of this life stage is the development of a self-identity. This is marked as an critical transition period when young adults embrace their newly found independence. Newly found independence has been shown to increase autonomy in decision-making, including those decisions associated with weight management (Fedewa et al., 2014; Nelson et al., 2008).

With newly found independence comes more responsibilities that can be overwhelming to young, inexperienced adults and it is reasonable to expect this transition period to be somewhat disconcerting (Swanson, 2015). One study found social and physical environments experienced by college students actually promote health- compromising behaviors, including those known to impact weight management such as dietary intake, physical activity, stress, and sleep (Das & Evans, 2014). Students unaware of these unhealthy lifestyle behaviors increase their risk of becoming overweight or obese and therefore may benefit from weight management interventions (Swanson,

2015).

Lack of Time. Among college students, lack of time is a major perceived barrier to being physically active and eating right in the university setting (Swanson, 2015).

Students continue to struggle to find appropriate times for academic demands, social demands, and work obligations.

Academic Demands. Busy college students may only have limited time in the day to dedicate to physical activity beyond the classroom and homework and as a result, most do not meet physical activity guidelines (Claxton & Wells, 2009; Swanson, 2015).

According to a survey, the average daily hours spent on educational activities was approximately 3.5 hours (United States Department of Labor, 2016). Recent data found that 28.1% of college students did not participate in any moderate or vigorous physical activity, and another 28.6% only participated in physical activity 1 to 2 days a week

(Claxton & Wells, 2009). One student stated, “my coursework is incredibly demanding, much more so than high school and I don’t want to sacrifice my studying time to exercise” (Das & Evans, 2014). These studies suggest the need for prevention interventions at the collegiate level (Claxton & Wells, 2009). In order for a student to fully devote themselves to their academic pursuits, other activities may be sacrificed or left little to no time to complete. Hence why students may feel they do not have time to prepare foods themselves or devote time to physical activity.

Social Demands. In addition to academic demands, maintaining or developing an active social life also takes top priority. A recent study found college students in their first semester of college spent on average 12 hours or more socializing. Although hours spent socializing steadily declined after the first semester, social demands remained a priority to students (Thibodeaux, et al., 2017). One student stated, “I’m busy with my classes and my social life so sometimes it is hard to fit in all the ‘good’ things you’re supposed to do” (Das & Evans, 2014). Devoting time to school work and managing time with family and friends can become overwhelming and time consuming for college students. Students note behaviors of others often influence what and when they eat and that social situations (Das & Evans, 2014). Students recognize going out to dinner as a major social event and typically associate these events with overeating and eating

unhealthful food choices such as fast food and alcohol (Greaney et al., 2009; Swanson,

2015).

Work Obligations. Work obligations also make it difficult for college students to adhere to nutrition and physical activity recommendations (Greaney et al., 2009). In addition to academic and social demands, working students often experience fatigue and excessive sleepiness, and feel they do not have enough time and will to follow healthy lifestyles. One study identified 74% of undergraduates work an average of 25.5 hours per week while going to school, and as a result, sedentariness and reduced sleep were commonly observed in this population (Gorgulho et al., 2012; Riccobono et al., 2002).

Another study analyzed working students who were engaged in at least six work hours daily, five days a week. Results indicated working students had poor diets (high intake of sodium and sugar and low consumption of fruits and whole grains), resulting in an inadequate nutritional status and an increased risk of obesity and chronic diseases when compared to non-working students based on their dietary intake report. Results indicated that the nutritional status of the working students was related to increased rates of overweight and obesity: 31.8% and 47.6% respectively of females and males were overweight; and 4.6% and 4.8% respectively of females and males were obese (Gorgulho et al., 2012).

Dietary Choices. College students continue to make poor dietary choices that contribute to energy imbalance (Dingman et al., 2014). Poor dietary choices including frequent fast food consumption, dining out, and alcohol consumption are factors effecting students’ risk of becoming overweight/obese.

Fast Food Consumption/Dining Out. Frequent consumption of fast food meals by college students appears to be another factor contributing to obesity. Fast food typically refers to food that is quickly prepared, purchased in self-service from restaurants with precooked ingredients, and served in a packaged form to the customer to take-away such as burgers (Lin et al., 1997). The large fast food availability in current college environments has been shown to contribute to fast food meal consumption and increase students’ risk for becoming overweight or obese (Dingman et al., 2014). This is because take away meals are typically high in calories, saturated fat, sugar, and sodium, and have been associated with increased body fatness, weight gain, and increased body mass index (BMI) (Powell et al., 2012; Goffe et al., 2017). Exposure to these easily- accessible fast food options increases the likelihood of students eating out or participating in poor nutrition behaviors (Kim, Hertzman & Hwang, 2010). Also, due to relatively inexpensive costs and quick, convenient service, fast-food restaurants have become the

“go to” for most college student meals (Kim, Hertzman & Hwang, 2010). According to a study most young adults have reported eating meals at fast food restaurants 1-3 times weekly (Morse & Driskell, 2009). Because of convenience, easy-accessibility and low- cost, high demands for fast food availability has caused an influx of fast food business into college campuses. Consistently popular fast food options include: Subway, Chipotle,

McDonalds, Taco Bell, Chick-Fil-A, Dairy Queen, Arby's, and Pizza Hut (Merrero,

2016).

Alcohol Consumption. Studies have also identified a relationship between alcohol use and obesity risk (Bryant et al., 2012; Burke et al., 2010). Heavy drinking among

college students continues to be a public health concern for colleges and universities throughout the U.S. According to a study, approximately 76% of college students have consumed alcoholic beverages in the past year and roughly 63% have drunk alcohol in the past 30 days, with 40% getting intoxicated during that time (Johnston, O’Malley,

Bachman & Schulenburg, 2009). One study identified a disturbing blend of diet-related behaviors with alcohol consumption such as self-imposed food restriction, poor dietary choices, and excessive binge eating (Barry, K. & Gardner, 2012). In addition, college students who engaged in frequent alcohol consumption were more likely to participate in binge drinking and unhealthy dietary behaviors such as excessive calorie consumption via fast food (high in added-sugar, added-fat, and sodium) (Burke et al., 2010).

Lack of Nutrition Knowledge. The internet contains a plethora of nutrition information. The general population is bombarded with both credible, and misleading or inaccurate nutrition messages making it difficult to discern appropriate recommendations

(The American Dietetic Association, 2006). Therefore, having a nutrition education background in high school my help college students as well as other populations identify accurate vs. misleading nutrition recommendations on the internet. According to the

Ohio Department of Education, high school students are only required to take one-half unit, or one semester (approximately 36 weeks) of health to graduate. Under this health course there are numerous topics discussed; nutrition being one of the topics. Although nutrition is a required part of the high school curriculum, the question remains whether one semester of health is enough to provide students with enough nutrition education to make healthy lifestyle choices after they graduate.

Credible Sources. Credible online sources include the CDC, WHO, USDA, and

Registered Dietitians. These sources provide accurate and balanced information enabling users to make well-informed, healthy choices. In addition, they provide population-wide health interventions (most available on the internet) with aims to improve the quality and quantity of dietary choices by providing sound nutrition and dietary information (Pollard et al., 2015). Although reliable sources like these are available, an enormous amount of misleading nutrition information is still out there. As use of the internet has grown

(especially among young adults), the potential to reach a large number of people has made it appealing for dissemination of nutrition interventions (Pollard et al., 2015).

Non-Credible Sources. Online health interventions or found in social media platforms have the capacity to influence voluntary behavior change regardless of the nutrition claim reliability (Cugelmen et al., 2011). The ability to express personal opinion and promote “healthy behaviors” can be problematic because it allows any user to make false nutrition claims- containing erroneous, incomplete, or misleading evidence without any scientific basis at all (The American Dietetic Association, 2006; Chau et al.,

2018). FD are an example of false or misleading health or therapeutic claims. FD involve unreasonable or exaggerated beliefs that eating (or not eating) specific foods, nutrient supplements, or combinations of certain foods may cure disease, convey special health benefits, or offer quick weight loss. Many people who promote false nutrition claims may themselves be victims of misinformation and may sincerely believe that they are providing accurate information. Consequently, these claims may be harmful to a consumer’s health and general well-being (The American Dietetic Association, 2006).

Overview of Fed vs. Fasted Metabolic States

There are three macronutrients: carbohydrate, protein, and fat, each of which play a major role in energy metabolism. During fed and fasted states, distinct metabolic processes are in place to properly facilitate energy for current needs and to make stored energy is available for future demands (Bender & Mayes, 2016). If there were no method in place to store excess energy, it would be necessary to eat constantly in order to meet energy demands. Consuming meals periodically throughout the day provides a continuous supply of energy (obtained from macronutrients) to all organs- one important organ being the brain. After consuming a meal, the body experiences a

“fed metabolic state.” Several hours without consuming a meal (fasting intensifies at approximately 18 hours), the body experiences a “fasted metabolic state” (Bender &

Mayes, 2018). In order to understand why certain metabolic processes, occur during these states, the function/purpose of each macronutrient must be addressed. The following sections provide an overview of the macronutrients and discuss the differences between each nutrient and their role in energy metabolism during fed and fasted states.

Overview of Macronutrients

Each of the macronutrients, carbohydrate (CHO), protein (PRO) and fat has a unique set of properties that influence health, but all are a source of energy (Carreiro et al., 2016). The optimal balance of their contribution to the diet has been a long-standing matter of debate. Table 2. displays current recommendations for consumption of each macronutrient versus actual intake of each macronutrient among young adults. Although

there are different health implications of diets that emphasize one macronutrient over another, from a body weight perspective, energy is the common denominator. Energy yield from each macronutrient differs. Table 3. provides the energy equivalent per gram for each macronutrient where fat contains the most energy per gram. One key question still being investigated is whether the unique properties of proteins, fats and carbohydrates hold particular implications for energy balance.

Table 2

Mean Dietary Intake of Macronutrients in Adults Aged 20 Years and Older

Macronutrient Women (% of total daily calories) Men (% of total daily calories) Carbohydrate 49.6 47.4

Protein 15.6 16.1

Fat 33.7 33.6

(Center for Disease Control and Prevention, 2017).

Table 3

Energy Equivalents Per Gram for each Macronutrient

Macronutrient Calories per Gram

Carbohydrate 4

Protein 4

Fat 9

Alcohol 7

(Gropper & Smith, 2013)

Carbohydrates. CHO are considered the major source of energy fuel in the average human diet supplying half or more of the total caloric intake (Gropper & Smith,

2013). CHO include both simple sugars (monosaccharides) such as glucose, fructose, and galactose, and complex carbohydrates (polysaccharides) such as starch, glycogen, and cellulose (Bender & Mayes, 2018). Of these, glucose is the body’s most readily available source of energy. This is because glucose requires minimal steps to break down, making it a quick nutrient to absorb and use as an immediate energy source. One particularly important organ that uses glucose as an energy source is the brain. Normal blood glucose levels are <200 mg/dL, where fasting blood glucose levels range from

70mg/dL-100mg/dL. In order to supply adequate fuel to the brain, blood glucose levels must remain above 70 mg/dL (Litchford, 2017). Blood glucose levels are controlled by two hormones, insulin and glucagon, both by which are secreted by the pancreas.

When blood sugar levels begin to drop past homeostatic levels, glucagon is secreted by the pancreas. In contrast, after a meal glucose levels begin to rise, and insulin is then secreted from the pancreas. After insulin binds to the cell receptor, glucose can be absorbed by the cell and begin a process called glycolysis (Bender & Mayes, 2018;

Gropper & Smith, 2013). Glycolysis is the pathway by which glucose is broken down into a molecule called pyruvate. In an aerobic environment, pyruvate is quickly converted to acetyl-coA which in turn initiates the Tricarboxylic Acid Cycle (TCA cycle)- a common pathway nutrients enter to be oxidized to CO2 and H2O with the accompanying release of energy in the form of Adenosine Triosephosphate (ATP). In order to send the necessary reducing equivalents (NADH & FADH) and energy, or

ATP. to the oxidative phosphorylation stage, the TCA cycle must receive acetyl-coA.

During oxidative phosphorylation (or the electron transport chain), reducing equivalents are oxidized, hereby releasing energy used to generate ATP. If CHO are consumed in excess during glycolysis, glucose is converted into glycogen and stored in the skeletal muscle and liver for later demands through a process called glycogenesis.

If, however, glycogen stores meet full capacity (glycogen storage capacity in man is approximately 15g/kg body weight and can accommodate a gain of approximately 500g

(Acheson et al.,1998) excess glucose is converted and stored as fat in the form of acyl- coA in adipose tissue (Bender & Mayes, 2018).

Protein. PRO is made of amino acids, which the body must have to synthesis its own variety of proteins and nitrogen-containing molecules that make life possible

(Gropper & Smith, 2013). There are 20 different types of amino acids, each one identified in a variety of different ways. Aside from being a metabolic fuel source, amino acids each play a major role in the development, structure, and function of all cells in the body. Examples of molecules comprised of amino acids include: cell signaling receptors, signaling molecules, structural members, enzymes, intracellular trafficking components, extracellular matrix scaffolds, ion pumps, ion channels, oxygen and CO2 transporters, hair, nails, and skin (Bender & Mayes, 2016). Although protein can be converted to acetyl-coA and used as an energy source, (through a process known as transamination) because of its’ numerous functional and structural roles, protein is typically spared until all other energy sources are depleted. If consumed in excess, proteins are converted into fat and used to build energy reserves.

Fat. Dietary fat is the densest source of energy per gram. Dietary fat is in the form of monounsaturated (MUFA), polyunsaturated (PUFA), saturated (SFA), and trans (TFA) fatty acids. These fatty acids differ in structure (Table 4. illustrates structural differences) and have many important roles in signal-transduction pathways, cellular fuel sources, the composition of hormones and lipids, the modification of proteins, and energy storage within adipose tissue (Gropper & Smith, 2013). Metabolism of dietary fat begins in the intestine where ingested long-chain fatty acids are broken down or emulsified by bile acids secreted by the gallbladder, separating fatty acids from glycerol backbones. These free fatty acids can be used as a direct energy source or stored in the form of triglycerides for later metabolic demands. The process of synthesizing fat from dietary fat as well as other dietary sources is called lipogenesis.

Triglycerides (or the storage form of fat) are a highly concentrated form of energy that accounts for 95% of all dietary fat (Gropper & Smith, 2013). If consumed in excess, fat synthesis and storage is accelerated leading to increased adiposity. Although fat is abundantly stored throughout the body, breaking down fat stores for energy (otherwise known as by β-oxidation or lipolysis) and converting stores to acetyl-coA, requires many steps, and takes time. Therefore, in instances when the body needs immediate energy, glucose is always utilized as primary energy source.

Table 4.

Structure of Long-Chain Fatty Acids

Type of Fatty Acid Number of Double Bonds Diagram

Saturated 0

Monounsaturated 1

Polyunsaturated >1

(Gropper & Smith, 2013).

Fed Metabolic State

The “fed metabolic state” occurs several hours after consuming a meal. During this time the body is digesting, or breaking down food, and absorbing the nutrients. In a fed state, although the first stages require catabolic processes (breaking down complex molecules into smaller molecules), anabolic processes (building of molecules) exceed these processes. This is because, once each nutrient is broken down by its specific pathway, each nutrient is quickly shipped, and stored as energy in various organs (Gropper & Smith, 2013). Figure 1. illustrates how each macronutrient is broken down, converted into a molecule called acetyl-coA, and shipped to the TCA cycle. Depending on the amounts and types of nutrients ingested, the absorptive state can linger for up to four hours. During this state various anabolic processes take place in order to facilitate energy storage for future metabolic demands. Such anabolic processes include: glycogenesis, protein synthesis, and lipogenesis. Nourishing the body with the appropriate amount and type of macronutrient helps promote the usage of highly available sources (such as glucose) before tapping into unfavored stores (muscle

tissue or the amino acid pool) or converting molecules into ketone bodies (KB) (Bender

& Mayes, 2018).

Figure 1. Outline of the Pathways for the Catabolism of Carbohydrate, Protein, and Fat into Acetyl-CoA (Bender, Rodwell et al., 2018)

Fasted Metabolic State

In a “fasted metabolic state” the body is entering a catabolic state where the breaking down of energy stores is required to stabilize a homeostatic environment

(Gropper & Smith, 2013). Common fasting states occur during sleep, or when meals are skipped during the day. During these periods, the body is not receiving energy through dietary sources and therefore must rely on its energy stores to provide fuel to

various organs such as the brain. As glucose levels in the blood begin to drop, insulin levels also drop. During this period the pancreas secretes glucagon which inhibits the glycogenesis and stimulates the breakdown of stored glycogen back into glucose; a process known as glycogenolysis. When glycogen stores begin to run low, lipolysis or the breakdown of long chain fatty acids is accelerated. During this state, long-chain fatty acids are cleaved through a process called β-oxidation. The resulting product of

β-oxidation is acetyl-coA which can further enter the TCA cycle and in longer states be converted into KB. This increased use of fatty acids is important because it decreases the overall glucose requirements of the cells (Bender & Mayes, 2018). In addition, gluconeogenesis, or the process of generating glucose from non-carbohydrate sources, is also initiated with lactic acid, glycerol, and alanine serving as primary energy fuel sources. However, when the body is deprived of nourishment for an extended period of time, metabolic fuel shifts occur again, this time in an effort to preserve body protein and find additional fuel sources for the brain. The protein-sparing shift at this point is from gluconeogenesis to lipolysis, as fat stores become the major supplier of energy.

This causes the blood level of fatty acids to increase as they are transported to organs such as the heart, liver, and skeletal muscle (Bender & Mayes, 2018). But because fatty acids cannot cross the blood-brain barrier, the brain cannot utilize fatty acids as any energy source (Mercola, 2017). Therefore, the brain adapts to using KB as an energy source. KB comprise of three water-soluble molecules containing a ketone group that is produced by the liver (Bender & Mayes, 2018). The three KB acetoacetate, β- hydroxybutyrate, and acetone, are products of a process called ketogenesis.

Ketogenesis produces these molecules in response to an accelerated fatty acid oxidation in combination with impaired carbohydrate intake or impaired carbohydrate use. The steps of KB formation, which occurs in the mitochondria, are represented in Figure 2.

Normally, KB concentration is low (fed state: <0.1 mm/L; fasted state: 0.1-0.3mmol/L) however, as carbohydrate use diminishes and oxidation of fatty acids accelerates

(leading to an accumulation of acetyl-coA), KB become the primary fuel source (Volek

& Phinney, 2012). KB acetoacetate and β-hydroxybutyrate are not oxidized further in the liver but instead are transported by the blood to peripheral tissue, where they can be converted back to acetyl-coA and oxidized through the TCA cycle. The reversibility of

β-hydroxybutyrate reaction to convert acetoacetate to acetyl-coA reveals how KB can serve as a source of fuel in these tissues. As starvation continues, fatty acids and triglyceride stores are used to create KB for the body to continuously use. This prevents the breakdown of proteins that serve as carbon sources for gluconeogenesis.

However, once fat stores are fully depleted, proteins from muscles are released and broken down for glucose synthesis. Therefore, the overall survival is dependent on the amount of fat and protein stored in the body (Bender & Mayes, 2018).

Overview of Fad Diets in College Students

Ongoing research of short-term unhealthy weight loss methods such as FD including restrictive dieting and dietary restraints (fasting, diet pills, laxatives, or self- induced vomiting) have been identified among college students (Hawks et al., 2008).

According to a study, 51.3% of college students indicated that they were trying to lose weight, 35% of which dieted to lose weight and 30% used a combined approach of diet

and exercise to lose weight (The American Health Association, 2009). Among various quick weight loss methods, one study found 40% of females and 13% of male college students reported have tried a FD. More than half of the students said results were short- lasting and unhealthy, 80% had no change in weight, or lost weight and gained it back, and 58% said they stayed on the diet for only a month or less and recognized FD as temporary weight loss solutions (Pedtke, 2001).

Popular FD utilized among young adults include: intermittent fasting, low-fat low-protein high-carbohydrate diets (Pritikin Diet), low-carbohydrate moderate-protein high-fat diets (KD and Atkins Diet), liquid protein-sparing modified fast diets

(Cambridge & “Last Chance” Diets), one or two food diets (Fiber or Fruit Diet), magic ingredient diets (Grapefruit or Magic Mayo Diet) and more (Crosser, 1985). Although college students recognize FDs as short-term, unsustainable weight loss methods, students continue to struggle to find the time to dedicate to healthy eating behaviors and exercise and therefore, turn to quick-fix methods such as FD to achieve rapid, optimal weight loss (Greaney et al., 2009; Swanson, 2015; Pedtke, 2001). One of the most popular FD, the KD, recognized as a low-carbohydrate moderate-protein, high-fat diet- aims to shift energy metabolism to enhance fat metabolism and utilization to induce fat loss (Paoli, 2014). It is important to note, FD can be potentially harmful to users, and impose certain health risks in times of extreme calorie restriction and dietary restraints

(Gupta, 2017).

The Ketogenic Diet

The KD aims to mimic biological changes associated with fasting, such as increased production and usage of KB and decreased usage of glucose (The Academy of Nutrition and Dietetics, 2017). As previously mentioned, KB formation increases during prolonged periods of fasting and starvation resulting in a metabolic state of ketosis. The livers ability to deliver KB to peripheral tissues such as the brain and muscle is an important mechanism for providing fuel to these organs during these periods (Gropper & Smith, 2013). The duration of KD may range from a minimum (to induce the physiological ketosis) of 2–3 weeks to a maximum (following a general precautionary principle) of many months (6-24) (Paoli, 2014).

History and Original Use

KD’s were a common practice in the treatment of epilepsy through the 1920’s and 1930’s based on findings that prolonged periods of fasting reduced seizure activity in patients diagnosed with the disease (Wheless, 2008). Although mechanisms by which how KD impacts seizure control are still not fully understood, results from rodent and human studies offer multiple hypotheses which can be classiﬁed into two categories: 1) alterations in energy metabolism, including a decrease in glucose concentration with an increase in fatty acid oxidation and KB production; and 2) alterations in neurotransmitter production, release and uptake (The Acadamey of

Nutrition and Dietetics, 2017). In 1938 pharmaceuticals grew in number and phenytoin was discovered as the first seizure-control drug. Because of this, KD fell out of favor due to the perceived complexity of adherence (Wheless, 2008). In 1994, KD grew in

popularity after a highly publicized story, and eventual movie titled First Do No Harm, about a boy who quickly became seizure-free on the KD. The resurgence in use of the

KD led to the development of less restrictive versions of the classic KD intended to enhance compliance (Wheless, 2008).

Figure 2. Conversion of Acetyl-CoA to Ketone Bodies and Interconversion of Identified Ketone Bodies. (Gropper & Smith, 2013).

Current Use of the Ketogenic Diet for Weight Management

Current evidence also suggests there is an increased interest in KD for weight management (Abbasi, 2018; Bueno et al, 2013). In overweight/obese patients, KD treatment had shown greater weight loss as compared to other FD (Khandelwal et al.,

2017). The possible mechanisms for higher weight loss may be controlled hunger due to higher satiety effect of proteins, direct appetite suppressant action of KB, and changes in circulating the level of several hormones such as ghrelin and leptin which controls appetite (Gibson et al., 2014). Other mechanisms proposed are reduced lipogenesis, increased lipolysis, greater metabolic efficiency in consuming fats highlighted by the reduction in the resting respiratory quotient, increased metabolic costs of gluconeogenesis, and the thermic effect of proteins (Gibson et al., 2014).

However, because of the broad lack of knowledge about the physiological mechanisms involved in KD, many researchers are concerned about its long-term health affects

(Paoli, 2014; Martin et al., 2011; Moreno et al., 2016).

Types of Dietary Fat Consumed on the Ketogenic Diet

When it comes to the KD, the type of dietary fat consumed is a key factor influencing an individual’s ability to maintain a metabolic state of ketosis. Certain types of dietary fat help to facilitate processes that are in favor of ketosis because these fats tend to be oxidized more rapidly and efferently over others (Volek & Phinney,

2012; Mercola, 2017).

Fats to Consume. Fatty acids that make up the majority of triglyceride in human adipose tissue consist of MUFA (55%) and SFA (27%) and least from PUFA

(18%). As an individual becomes more efficient utilizing ketone bodies and fatty acids as a primary fuel source, individuals become “keto-adapted.” Therefore, the body is consistently storing MUFA and SFA for later metabolic demands or utilizing these fatty acids as a current energy fuel source. Thus, it is important to continuously supply the body with MUFA and SFA while keeping carbohydrates low and consuming both protein and PUFA in moderation (Volek & Phinney 2012). Examples of high-quality fat sources also with protein are included include: organic grass-fed butter and ghee, coconut milk, chicken fat, duck fat, coconut oil, medium-chain triglycerides (MCT), avocado oil, and extra virgin olive oil (Mercola, 2017). MCT oil in particular is another dietary fat emphasized in the KD. This is because MCT oil is able to diffuse across the intestinal membrane (therefore do not require additional steps to break them down) and go directly into the liver via hepatic portal. Once there, MCT are quickly converted into ketone bodies which are released into the bloodstream and transported throughout the body including the brain to be used as energy (Paoil, 2014; Gropper &

Smith; 2013; Mercola, 2017).

Fats to Avoid. It is important to adhere to these recommendations and avoid all industrial processed fats- including vegetable oils (canola, peanut cottonseed, corn, and soy)- as well as those found in commercial salad dressings, peanut butter, most mayonnaise, and anything processes or packaged (Volek &Phinney, 2012). It is also important that ingredients such as hydrogenated oils or trans-fat are avoided. Reasons for this is because foods such as these have been shown to disrupt omge-3 and omega-6 fatty acid balance, are highly susceptible for oxidation (which increase free radical

damage within the mitochondria), carry high levels of pesticides because most vegetable oils are extracted from genetically modified glyphosate-soaked plants, are highly volatile, and are harmful when subjected to heat (Mercola, 2017).

Different Types of Ketogenic Diets

The Academy of Nutrition and Dietetics recognizes various types of KD, all of which aim to reduce net carbohydrate intake and increase fat intake to alter metabolism.

Several variations of KD have been found as successful treatment methods in those suffering from epilepsy and are now also utilized as weight loss methods. These diets include: Classic KD, Modified KD, Modified Adkins Diet (MAD), Low Glycemic

Index Treatment (TT), and MCT. Table 5. provides an overview of these various types of KD and their overall macronutrient content in comparison to the 2015-2020 Dietary

Guidelines for Americans.

Classic Ketogenic Diet. The classic KD, generally recognized as the 4:1 ratio, is the most restrictive, requiring all foods and beverages to be carefully calculated and precisely weighed (McDonald et al., 2018). The Classic KD offers higher ketogenic potential compared to all other KD because carbohydrate and protein intake is extremely limited. Scarcity of these nutrients and greater intake of dietary fat helps to quickly alter and initiate metabolic processes that favor fat utilization in order to preserve carbohydrate stores and provide the brain with an alternative fuel source (KB). It is possible to use lower ratios of 3:1, 2:1 or 1:1 (referred to as a modiﬁed ketogenic diet) depending on age of the patient, individual tolerability, levels of ketosis and protein requirements (Williams et al., 2017). Ratios 4:1 and 3:1 are more carbohydrate and protein restrictive, inducing

ketosis more rapidly compared to modified KD ratios 2:1 and 1:1 Williams et al., 2017).

Although less restrictive ratios may not induce ketosis as quickly, such ratios are less complex and are seen to have a higher adherence rate (The Academy of Nutrition and

Dietetics, 2017).

Table 5.

Comparison of Daily Macronutrient Composition and Initiation Requirements Between Various Ketogenic Diets and the 2015-2020 Dietary Guidelines for Americans

Diet Type Fat (% of total daily Carbohydrate (% of Protein (% of calories) total daily calories) total daily calories) 2015-2020 Dietary 20-35 45-65 10-35 Guidelines for Americans Ketogenic Diet Ratios*

Classic KD (4:1) 90 2-4 6-8

Modified Classic KD 85-90 2-5 8-12 (3:1) Modified Classic KD 80-85 5-10 10-15 (2:1) MAD (1:1) 60-65 5-10 25-35

LGIT (1:1) 60-70 20-30 10-20

MCT (1:1) 60-70 20-30 10

*Ratio refers to grams of fat: carbohydrate + protein (Academy of Nutrition and Dietetics, 2017)

Modified-Atkins Diet and Low-Glycemic Control Treatment In both the

MAD and LGIT, fat is encouraged ideally composing 60%-70% of total daily calories.

The MAD, which was first introduced in 2003 in effort to ease implementation and

adherence to KD, is typically composed of a net 10–20g/day carbohydrate limit which is equivalent to a ratio of 1–2:1 of fat to protein plus carbohydrates (Williams et al.,

2017). It allows users more ﬂexibility and does not require the weighing of food portions nor an initial hospital stay for implementation (Academy of Nutrition and

Dietetics, 2017; Williams et al., 2017; Freeman et al., 2007).

In the LGIT, carbohydrates are limited to 40 to 60 g/ day from foods with a glycemic index <50 to prevent rapid changes in blood glucose and insulin levels.

Carbohydrates are encouraged to come from foods with high ﬁber contents, such as nonstarchy vegetables, nuts, and seeds, where fruits, breads, and starches are discouraged. Although protein is not restricted on either version, intake above the needs of the average adult (0.8 to 1.2 g/kg actual or adjusted weight for an adult) or above the dietary reference intake for age in pediatrics and adolescents may impact ability to maintain ketosis (Academy of Nutrition and Dietetics, 2017; Williames et al.,

2017).

Medium-Chain Triglyceride Diet. The MCT diet is more liberal than the classic KD diet due to high intake of ketone-boosting MCT rich fats, comprising up to

60% of total calories with less carbohydrate content (Academy of Nutrition and

Dietetics, 2017). Consumption of MCTs results in higher ketogenic potential due to ease of digestion and absorption, as they do not require bile salts for digestion; instead,

MCTs are absorbed directly through the enterocyte, rapidly transported into portal circulation, and subsequently converted to ketones by the liver (McDonald et al., 2018).

However, use of the MCT diet is less common and sometimes limited due to unpleasant

gastrointestinal side effects with consumption of high concentrations of MCT oil. In order to relieve symptoms, smaller amounts of MCTs are incorporated into other versions of the KD to enhance ketosis (The Academy of Nutrition and Dietetics, 2017;

Freeman et al., 2007).

Ketogenic Diet for Weight Management Benefits.

Studies show many significant health benefits in KD use for weight management. According to various studies, participants following a KD had improved hunger cues (increased satiety), significant weight loss, improved blood glucose levels and HbA1C, and improved lipid profiles (Castro et al., 2018; Moreno et al., 2016,

Martin et al., 2011; Johnstone et al., 2008; Hussian et al., 2012).

Improved Hunger Cues. Recent studies suggest the KD induces satiety -or the state of feeling full- more quickly and improves hunger cues – or the ability to listen to the body’s internal signals of hunger or fullness- significantly compared to non-KD diets

(or medium to high carbohydrate intake diets) and low-fat diets (LFD) (Martin et al.,

2011; Johnstone et al., 2008). One study (study A) analyzed 307 obese individuals ages

18-65 for two and half years. During the study, researchers observed changes in appetite ratings in two intervention groups; a low-carbohydrate diet (LCD/KD) and a LFD. The

LCD/KD consisted of a carbohydrate intake of 20 g/day in the form of low-glycemic index (GI) vegetables with the rest of daily kcals coming from fat and protein sources.

The LFD included 1200–1500 and 1500–1800 kcal/day diets, 30% kcal from fat, 15% from protein and 55% from carbohydrate. Results of the study showed that the LCD group was bothered significantly less by hunger with an increased satiety compared to the

LFD group (p-values > .07). In the LCD/KD group, men reported larger decreases in hunger, F(1,327) = 7.59, p = .006, being bothered by hunger, F(1, 325) = 5.39, p = .021, wanting to eat in response to seeing or smelling food, F(1, 320) = 17.74, p < .0001, and thoughts about food, F(1,313) = 5.90, p = .016. compared to women (Martin et al.,

2011). Another study (study B) analyzed twenty obese men aged 20–65 years old following either a low-carbohydrate diet (LCD/KD) or a medium-carbohydrate diet

(MCD) for four weeks. The LCD/KD consisted of 66% kcals from protein, 4% kcals from carbohydrate, and 66% kcals from fat. The MCD consisted of 30% kcals from protein, 35% of kcals from carbohydrates, and 35% of kcals from fat. Results showed subjects felt significantly (P = 0.014) less hungry while following the LC/KD than while following the MC diet.

Weight Loss. Strong supportive evidence suggests that the use of KD in weight loss therapy is effective (Paoli, 2014). Recent studies show subjects who followed the

KD for weight loss had significant weight loss results, decreased adiposity, and a lower

BMI compared to non-KD and very-low calorie diets (VLCD) (Castro et al., 2018;

Moreno et al., 2016). One study (study C) analyzed 20 obese patients (12 female) aged

18-65 following a very low-calorie ketogenic diet (VLCKD) diet for four months. The diet consisted of 600–800 kcal/day, carbohydrates (<50 g daily from vegetables), lipids

(only 10 g of olive oil per day), and high biological-value proteins ranged between 0.8 and 1.2 g per each kg of ideal body weight. At the end of the study, the dietary-induced changes in body composition were 7.7 units of BMI lost and 18 kg of fat mass (1.2 kg of visceral fat mass) lost (Catsro et al., 2018). Another study (study D) analyzed a group of

45 obese patients aged 18-65 four two years who were randomly allocated in two groups: either the VLCKD, or VLC group. The VLCKD consisted of 600–800kcal/day, carbohydrates (<50g daily from vegetables), lipids (only 10g of olive oil per day), and high biological value proteins ranges between 0.8 and 1.2g per each kg of ideal body weight. The VLC diet consisted of calories between 1400 and 1800kcal/day, 45–55% of daily kcal from carbohydrates, 15–25% from proteins, and 25–35% from fat. At the end of the two years, the VLCKD group had induced a greater reduction in body weight

(−12.5kg), waist circumference (−11.6cm), and body fat mass (−8.8kg) and visceral fat

(−600g vs. −202g; p<0.001) than the VLC group (−4.4kg, −4.1cm, and −3.8kg, respectively; p<0.001) (Moreno et al., 2016).

Improved Blood Glucose Levels and HbA1C. Although the effect of the KD on glucose homeostasis is controversial, KDs have been shown to help regulate blood glucose levels and HbA1C levels -or the measurement of glucose in the blood in the last

2-3 months- in overweight and obese patients with and without T2DM (Cicero et al.,

2015; Hussian et al., 2012). One study (study E) investigated blood glucose levels in

T2DM patients following a KD for one year. A total of subjects aged 30-69 years old with a BMI between 27-37 followed a KD that consisted of a high biological protein formulation of milk/egg/legumes origin (peas and NO OGM soybeans), with a content of 15–18 g in proteins, 2–6 g in carbohydrates, 3 g in fats for a caloric intake of 100 kcal. Additionally, vegetables were allowed. Results showed patients had signiﬁcantly improved fasting blood glucose (FBG) levels from baseline to 4 weeks (-8.7 ± 15.3 mg/dL, p\0.001) where levels showed no change after one year. In addition, HbA1c

levels improved from baseline to 3 months (-0.3 ± 0.7 mg/dL, p\0.001) and held steady after one year of observation (Cicero et al., 2015). Another study (study F) investigated changes in blood glucose levels among 307 overweight and obese (102 with T2DM) participants over the course of six months. Subjects were 18 years and older and were assigned to a low-calorie diet (LCD) or low -carbohydrate ketogenic diet (LCKD). In the LCKD, carbohydrates were limited to <20g/day, and the remaining kcals from protein and fat sources. The LCD group was given appropriate guidelines and a sample LCD menu of 2200 calories to follow. Results showed blood sugar levels signiﬁcantly decreased in both groups. However, the effectiveness of the

LCKD was much greater (P < 0.0001) in the T2DM LCKD group (% change of -6.1) compared to the T2DM LCD group. Similarly, HbA1c levels signiﬁcantly decreased in both T2DM and non-diabetic patients in the LCKD compared with the LCD in both groups (Hussian et al., 2012).

Improved Lipid Profile. KDs have also shown to help improve lipid profiles such as blood triglyceride levels and cholesterol (lower LDL-cholesterol and increase

HDL-cholesterol) (Tay et al., 2014; Hussian et al., 2012; Cicero et al., 201). One study

(study G) analyzed 93 obese adults with T2DM for six months. Subjects were assigned to a hypocaloric low-carbohydrate diet (HLCD) (14% carbohydrate [<50 g/day], 28% protein, and 58% fat [<10% saturated fat]) or an energy-matched high- carbohydrate diet (EMHCD) (53% carbohydrate, 17% protein, and 30% fat [<10% saturated fat]) combined with structured exercise. Results showed diet composition signiﬁcantly affected triglycerides (P = 0.001) with ﬁvefold greater reductions in the HLCD group

compared to the EMHCD group with greater increases in HDL-cholesterol (P= .007) compared to the EMHCD group (Tay et al., 2014). In addition, study F showed in

T2DM patients and non-diabetic participants following the LCKD, both groups had significant decreases (P < 0.0001) in triglycerides, total cholesterol, and LDL- cholesterol levels, whereas the HDL-cholesterol level was significantly (P < 0.0001) increased from baseline (Hussian et al., 2012). Also, study E participants had improved lipid parameters where LDL-cholesterol significantly improved from baseline (-19.5 ±

16.9 mg/dL,p\0.001) with no change after one year of observation. A similar trend was also observed for triglycerides (-23.4 ± 30.2 mg/ dL, p\0.001), while HDL-cholesterol improved from baseline to 12 months (3.5 ± 3.3 mg/dL, p\0.001) (Cicero et al., 2015).

Ketogenic Diet for Weight Management Issues

Although research suggests KD may be used as a successful method for weight loss and short-term weight management, studies show adherence rates of individuals following the KD long-term decline after initiation (Paoli, 2014; Bonnie et al., 2003).

In addition, there is a lack of studies addressing the potential long-term health outcomes of individuals following the ketogenic diet for weight management.

Adherence & Compliance Issues. KD compliance issues stem from the extreme dietary restrictions (especially carbohydrates) expected of individuals in order to maintain a state of ketosis, steady weight loss, or a certain weight (Volek & Phinney,

2012). Multiple studies have addressed patient compliance issues and have created less restrictive versions of the KD (still enabling ketosis) in hopes of increasing KD adherence rates (The Acadamey of Nutrition and Dietetics, 2017; Mobbs et al., 2013).

More liberal versions of the KD, such as the MAD, have shown to have higher adherence rates versus the classic KD (Mobbs et al., 2013). In addition, because carbohydrates are restricted on the KD, health care professionals are working to create meals that mimic carbohydrate rich foods, which could improve overall compliance to the diet (Bonnie et al., 2003). Although these options help to decrease adherence complexity of KD, significantly reducing total intake of any macronutrient has the possibility of reducing an individual’s ability to follow the diet long-term (Williams et al., 2017).

Lack of Long-Term Health Outcomes. Typically, once a study is concluded, participants are no longer monitored or followed-up with any additional questions

(unless stated prior to study initiation) (International Review Board Policies, 2019).

Even when researchers include a follow-up, it might not provide enough insight regarding a patient’s long-term health outcomes. This leaves researchers with many questions regarding the study participants long-term health outcomes once the study is completed. For example, one study explained in order to maximize adherence to study visits, participants were provided with an appointment schedule at the commencement of the study and received appointment reminders (phone calls or text messages) before visits (Tay et al., 2015). This kept participants accountable throughout the study intervention, and therefore, researchers had higher adherence rates of participants on the KD. However, after remission of the study, questions regarding the participants adherence and health outcomes post-research remained uninvestigated. Therefore, it

may be appropriate to question whether the KD proposes additional negative or positive health outcomes for weight management long-term.

Ketogenic Diet for Weight Management Short-Term Risks

Gastrointestinal side effects are common reasons for KD discontinuation (The

Acadamey of Nutrition and Dietetics, 2017). Mild side effects and tolerance concerns can occur during the ﬁrst few days and weeks after KD initiation. Side effects include: fatigue, headaches, dehydration, nausea, vomiting, constipation, acidosis, hyperproteinemia, or hypoglycemia (Williams et al., 2017). If these symptoms occur, health care professionals recommend an oral citrate or sodium bicarbonate to buffer acidosis, and/or the diet ratio can be decreased to improve tolerability and palatability.

It is important to note that many oral citrate products contain signiﬁcant amounts of carbohydrate, which must be calculated in the diet (The Acadamey of Nutrition and

Dietetics, 2017). Hyperproteinemia typically caused by patient food refusal or insufficient consumption of protein rich foods can be resolved by altering the patient’s dietary intake (changing composition or supplementing) (Suo et a., 2012). Transient hypoglycemia is often a complication of the KD, usually in the initial period of fasting but also during the initial step-wise increase in caloric intake in the non-fasting protocol.

However, most patients experiencing this recover without assistance and show no hypoglycemic symptoms (Kang et al., 2004). Once tolerance has been established, the diet may be adjusted to increase ketogenic potential if needed for enhanced efﬁcacy

(The Acadamey of Nutrition and Dietetics, 2017; Williams et al., 2017).

Ketogenic Diet for Weight Management Long-Term Risks

Studies investigating long-term risks of the KD are scarce, however there is evidence suggesting adherence to the diet long-term could negatively impact overall health. Negative long-term health outcomes range from mild to moderate diagnosis such as nutritional decencies or imbalances, to extreme life-threatening complications and death. Long-term risks can occur when following KD if not monitored closely and vary tremendously on the current health status of the individual following the KD (Kang et al.,

2005).

Nutrient Deficiencies. Vitamin and mineral deﬁciencies have been reported following a restrictive carbohydrate diet such as the KD and can cause serious health complications if unaddressed. Because the KD does not allow starchy fruits or vegetables; breads, pasta, or grains; or sources of simple sugars, the food preparation can be onerous for parents and patients, must pay great attention to selecting, weighing, and cooking every meal or dietary component (Rogovik et al., 2010). Commonly seen deficiencies in those following the KD include: calcium, fiber, sodium and potassium.

Inadequate calcium intake can further impair bone mineralization in patients already at risk of osteopenia or osteoporosis due to antiseizure therapy (Kang et al., 2004). A lack of fiber in the diet due to restrictive carbohydrate intake (complex carbohydrates tend to have high concentrations of carbohydrates) can cause constipation (Rogovik et al., 2010).

In addition, sodium and water loss may be reported because carbohydrate stores (which retain sodium and water) are restricted (Volek & Phinney, 2012). Therefore, patients on

the KD should receive recommended daily intakes of vitamins and minerals (in sugar- free formulations) if needed and monitor fluid intake closely.

Fatal Complications. Although not commonly seen, severe long-term complications have been recorded in patient’s following the KD. One study analyzed patients with various forms of epilepsy utilizing the KD (average duration of patients on the KD = 13.5 months) as a therapeutic treatment method over the course of twelve months. Results found out of 199 patients, five deaths were reported after conclusion of the study. Deaths were caused by lipoid aspiration pneumonia, serious infectious disease, and nutritional problems. Researchers, however, address such complications may not have been due to KD, but rather, deaths may have been indicative of the severity of the patient’s basic condition and of the increased morbidity and mortality whether they were on KD or not (Kang et al., 2005). Another study monitoring a similar patient population reported signs of acute pancreatitis- a rare but serious complication that is often fatal- while on the KD. Pancreatitis can be caused by hypertriglyceridemia and sometimes by the concomitant use of anti-epileptic drugs, especially sodium valproic acid (VPA).

Discontinuation of the KD and adequate supportive treatment are required for successful recovery (Kang et al., 2004; Williams et al., 2017). Other reported complications in alike populations include renal stones, and cardiac problems. Such complications may be due to the state of disease progression, nutrient malabsorption, and or nutrient deficiencies

(Kang et al., 2005).

It is important to note, most studies addressing long-term health (both negative and positive) outcomes of the KD focus primarily on patient populations suffering from

epilepsy, not weight management. These studies are complex and suggest complications stem mainly from the current disease state of the patient and the disease’s multifaceted etiology, not the KD (Kang et l., 2004; Kang et al., 2005; Williams et al., 2017).

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CHAPTER III

METHODOLOGY

Research Design

Purpose Statement

The purpose of this study was to: 1.) examine college student’s knowledge and perception of the ketogenic diet 2.) investigate college student’s usage of ketogenic diet at Kent State University.

Research Design

This was a descriptive, comparative, posttest only study analyzing the knowledge, perception, and use of the ketogenic diet (KD) among college students at

Kent State University’s main campus.

Sample

A convenience sample of 24,551 undergraduate and graduate students at Kent

State University was used in this research. Participants were recruited via email based on their current enrollment for Spring 2019 semester at Kent State’s main campus.

Inclusion criteria specified that participants completed the entire survey, they were between the ages of 18 and 26, and have heard of the KD prior to survey questionnaire administration.

Measurement Instruments

Qualtrics

The survey for this study was designed using Qualtrics software by the researchers. Qualtrics is an online software widely used for academic research; users are able to do many kinds of online data collection. Survey data obtained through

Qualtrics will be exported for further analysis in Statistical Package for Social Sciences

(SPSS) software version 24.

The survey questionnaire was divided into four main parts: 1.) demographic questions, 2.) general questions, 3.) knowledge questions, 4.) perception questions. The survey comprises of 43 questions and took the participants approximately 10-15 minutes to complete.

Part I Demographics: The first section of the survey contained nine questions seeking information regarding the student’s demographics. Students provided details about their age, sex, ethnicity, class rank, whether they’ve taken a college level nutrition course, major of study, height, weight, and current living arrangements.

Part II General: This section of the survey contained five questions about students dieting experience. Students were asked if they have ever tried a fad diet. Students were then asked if they have ever heard of the ketogenic diet. If the student answered “yes,” they continued the rest of the survey. If a student answered “no” they ended the survey.

Following this question, students were asked if they currently follow or have ever followed the ketogenic diet. If the student answered “yes” they continued the survey

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answering questions about the duration and result of their latest experience following the ketogenic diet. If the student answered “no” they skipped to the next set of questions.

Part III Knowledge of the Ketogenic Diet: This section contained 19 knowledge questions that were used to measure student’s knowledge of the KD. Students were asked questions about the history and definition (questions 1, 2, & 17), metabolism

(questions 3-10), diet components (questions 11 & 12), risks and benefits (questions

13-16 & 18) of the KD. Knowledge questions were asked in the form of true and false where students had the option to select “I don’t know.” Students were asked not to guess when answering the questions. If they did not understand or were not confident with their answer, they were asked to select the “I don’t know” option.

Part IV Perception of the Ketogenic Diet: This section of the survey contained

11 questions measuring student’s perception of the KD. Two questions were utilized as filter questions and were excluded leaving a total of nine questions in the final data analysis. A variety of questions were asked to grasp a better understanding of the student’s current feelings towards the KD. Students were asked to answer questions based on a 5-point Likert scale, where a response of (1) meaning strongly disagree and a response of (5) meaning strongly agree.

Procedures

Upon Kent State University International Review Board (IRB) approval, 24, 551 surveys were distributed to student email addresses using Qualtrics software. Student e-mails were obtained from the university’s Provost Office. Included in the e-mail was a hyperlink that directed students to the consent form and the survey. Participants

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must have voluntarily agreed to the consent form prior to starting the survey. The consent form provided a general overview of the survey, the name and contact information of the primary researcher, informed the participant that they were at minimal risk, and explained that they could withdraw from the study without penalty at any point. The survey ended if students did not voluntarily agree to the consent form.

The e-mail also provided details about the purpose of the study and explained that their participation would be valuable in understanding knowledge, perception, and usage of

KD in college students. Students were also informed in the e-mail that no personal identifiable information would be obtained with their responses (i.e., IP address or name) and that their participation would remain confidential throughout the entire study. Participants were informed if they chose to take the survey, that they would be automatically entered in for a chance to win a $25.00 gift card to Amazon. This participant would be randomly selected at the end of the study. A total of two e-mails were sent to students to increase participation in the study. An initial e-mail was sent out to students and a follow up email was sent out to students after one week. If students chose to unsubscribe to the e-mail, they did not receive a follow up e-mail.

The survey was active for two weeks before the survey hyperlink expired.

Statistical Analysis

Analysis of results was completed using the Statistical Package for Social

Sciences (SPSS) version 24. A 2x2x2 multifactorial ANOVA was used to analyze the independent variables (sex, major, and user category) differences and potential interaction effects among dependent variables (knowledge and perception). For

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knowledge, a mean knowledge score was calculated for each individual question.

Scores for the knowledge section were measured using a continuous scale. The knowledge questions were scored by identifying the correct answer as a score of one.

Incorrect answers or students who selected “I don’t know” for their response were scored a zero. Total knowledge score was calculated by the sum of all correct answers.

For perception, a mean score was determined by averaging student responses based on the 5-point Likert scale. If the total average score for each student was closer to one, the student had a ‘less favorable’ or lower perception score. If the student had a total average score closer to five, the student had a ‘more favorable’ or higher perception score. Total perception scores were calculated by the sum of all responses. Responses were also inverted (reversed scored) for questions that had negative loading. Data was considered significant at a value of p < 0.05.

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105

CHAPTER IV

JOURNAL ARTICLE

Introduction

The escalating overweight/obesity epidemic is a significant public health concern affecting about 40% of adults in the United States (U.S.) (Center for Disease Control and

Prevention, 2017). Obesity is associated with the development of numerous chronic disease such as, type 2 diabetes (T2DM), cardiovascular disease (CVD), hypertension

(HTN), cancer, arthritis, as well as other negative health outcomes (Marcia, 2018;

Schwartz, 2014). This ongoing rise of obesity in the U.S. proposes undeniable health risks for every population, especially college students (Fedewa et al., 2014). Factors contributing to overall energy imbalance among college students include stress, lack of time, poor dietary choices, physical inactivity, and lack of nutrition knowledge (Swanson,

2015). With such struggles, college students have turned to the internet -an easily accessible and convenient tool- to obtain information regarding potential weight management methods and nutrition-related advice/recommendations (Pollard, 2015).

The internet as well as other outside influences (such as family and friends) also strongly effect the direction students take in order to achieve their weight goals regardless of their own perception and beliefs (Pearson & Young, 2008).

One typical health related solution promoted today (i.e social media and television) are Fad Diets (FD); or non-credible temporary diet solutions that promise weight loss or other health advantages. Among weight loss methods, FD have gained popularity due to rapid and easy-fix weight loss results (Obert et al. 2017; Abbasi, 2018).

Consequently, despite the lack of knowledge of these FD (understanding potential risks, other complications etc.), students continue to engage in FD, and therefore, fail to adopt healthful eating patterns (Pearson & Young, 2008). One increasingly popular FD for weight loss is the ketogenic diet (KD); or a high-fat, low-carbohydrate, moderate protein diet that aims to force the body to breakdown fat instead of glucose (The Academy of

Nutrition Dietetics, 2017). Although KD was originally developed as a therapeutic treatment for patients suffering from epilepsy, because of its’ positive short-term health outcomes and accelerated weight loss, KD continues to grow in popularity as a weight management method (Paoli, 2014).

It is important to note that KD research is still developing and studies (>2 years) analyzing the long-term health risks associated with the KD is limited. Scarcity of these studies propose many unanswered questions regarding clinical impacts, safety, tolerability, efficacy, duration of treatment, and prognosis after discontinuation of the diet

(Gupta, 2017). For these reasons, those interested in the KD should take precaution and discuss this potential option with a dietitian or physician before self-administration

(Khandelwal et al., 2017).

The purpose of this study was to examine the knowledge, perception and usage of the KD among college students at Kent State University main campus. It was hypothesized that there will be differences in knowledge and perception among sexes, majors, and user groups. It was also hypothesized that there will be a difference in the usage of the KD among college students.

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Methodology

This descriptive, posttest only, multifactorial design study was conducted in order to understand the knowledge, perception, and usage of the KD among college students at midwestern university. The study received approval from the International

Review Board (IRB) for collection of survey responses and data assembly. This study was based on the data provided from students enrolled in Spring 2019 semester at Kent

State University’s main campus. This study focused on the young adult population

(ages 18-26), therefore students that did not fall into this age range were excluded from the study. In addition, students must have heard of the KD prior to the survey, if they had not heard of the KD before survey administration, these students were also excluded. Research data came from a survey questionnaire via Qualtrics that examined students’ demographics, general weight loss experience, perception of the KD and knowledge of the KD. A total of 24,551 emails were sent to students with 2,536 total survey responses. Final data collection consisted of approximately 1,131 students which included all majors, college levels, and part and full-time students.

Questionnaire

The survey questionnaire (found in appendix C) was divided into four main parts: 1.) demographic questions, 2.) general questions, 3.) knowledge questions, 4.) perception questions. The survey comprised of 43 questions and took participants approximately 10-15 minutes to complete.

The first section (Part I) of the survey contained nine questions seeking information regarding the student’s demographics. Students provided details about

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their age, sex, ethnicity, class rank, whether they’ve taken a college level nutrition course, major of study, height, weight, and current living arrangements.

This second section (Part II) of the survey contained five questions about students dieting experience. Students were asked if they have ever tried a FD. Students were then asked if they have ever heard of the KD. If the student answered “yes,” they continued the rest of the survey. If the student answered “no” they ended the survey. Following this question, students were asked if they currently follow or have ever followed the KD.

If the student answered “yes” they continued the survey answering questions about the duration and result of their latest experience following the KD. If a student answers “no” they skipped to question 15.

The third section (Part III) contained 19 knowledge questions that were used to measure student’s knowledge of the KD. Students were asked questions about the history and definition (questions 1, 2, & 17), metabolism (questions 3-10), diet components (questions 11 & 12), risks and benefits (questions 13-16 & 18) of the KD.

Knowledge questions were in the form of true and false where students had the option to select “I don’t know.” Students were asked not to guess when answering the questions. If they did not understand or were not confident with their answer, they were asked to select the “I don’t know” option.

The final section (Part IV) of the survey contained 11 questions measuring student’s perception of the KD. Two questions were excluded from the data analysis leaving a total of nine questions. A variety of questions were asked to grasp a better understanding of the student’s current feelings towards the KD Students were asked to

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answer questions based on a 5-point Likert scale, where a response of (1) meaning strongly disagree and a response of (5) meaning strongly agree.

Data Analysis

All data collected from student’s survey questionnaires was exported into

Microsoft Excel (Version 1805) and then transported into Statistical Package for the

Social Sciences version 24.0 (SPSS, Chicago, Illinois). Surveys that were incomplete were not included in the final analysis. Descriptive statistics were used to examine frequencies, percentages, means, and standard deviations of variables including students’ demographic characteristics. A 2x2x2 multifactorial ANOVA was used to measure the differences and potential interaction effects between independent variables

(sex, major, and user category) and dependent variables (knowledge and perception).

Data was considered significant at a value of p < 0.05.

Results

Of the 24, 551 emails sent to students, 2,536 students responded to the survey.

A total of 1,131 students were included in the final analysis, excluding a total of 1,364 students. Students were excluded from the study if they did not fall into the age range of 18-26 (n= 602), if they had never heard of the KD (n=501), or because they submitted an incomplete survey (n=302).

Table 6 shows a description of the demographic characteristics of students involved in the study. The majority of students were female, Caucasian, seniors in college, and had an average age of 20.69 + 2.11. Among college majors recorded, most

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students were non-health related majors, about one-third of students had taken a college level nutrition course, and 30% of students reported trying a fad diet (FD).

Table 6.

Demographic Characteristics of College Students Who Responded to the Ketogenic Diet Survey (N=1,131)

Sex n % Male 212 18.7 Female 919 81.3 Total 1131 100.0 Ethnicity na % Caucasian 992 87.7 African American 47 4.2 Hispanic/Latino 23 2.0 Asian 31 2.7 Middle Eastern 5 .4 Native American 1 .1 Other 29 2.6 Total 1128 100.0 Class Rank n % Freshman 230 19.5 Sophomore 236 20.9 Junior 230 20.3 Senior 278 24.6 Masters Level 140 12.4 Doctoral Level 27 2.4 Total 1131 100.0 Major n % Health Related 438 38.7 Non-Health Related 693 61.3 Total 1131 100.0 User Category n % User 205 18.1 Non-User 926 81.9 Total 1131 100.0 a = number of majors may differ due to incomplete responses

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Analysis of Ketogenic Diet Knowledge Among College Students

This section focuses on the knowledge of the KD among all college students. A total of 19 true and false questions were asked in this section. If the student answered the question correctly, they were scored a one. If the student answered the question incorrectly, or selected ‘I don’t know’, they were scored a zero. A total knowledge score was calculated by the adding up of all correct answers.

Table 7 displays the mean KD knowledge of college students within all groups.

Each sex was broken into two categories based on their major (health related or non- health related). These groups were then broken into two more groups based on their usage survey response: ‘user’ (those who answered either ‘yes I am currently following the ketogenic diet or ‘no I am currently not following but have used before’) and ‘non-

User’ (those who answered ‘no I do not currently follow nor have I ever used the ketogenic diet’). Only female (n= 919) and male (n=212) responses were included in the total count, therefore students who responded “other” (n=6) were not included in the final analysis. The overall mean, 7.98 + 4.37, score suggested students had below average knowledge scores of the KD.

Table 8 displays the KD knowledge in-between interaction effects of college students among all groups. Overall, results showed that health related majors had significantly higher knowledge scores versus non-health majors, and users had significantly higher knowledge scores versus non-users. There were no two-way or three-way interaction effects found between groups.

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Table 9 displays the KD knowledge scores by question among college students within all groups. Among all questions, the highest score was 100% and the lowest score was 9.7%.

Table 7.

Assessment of Ketogenic Diet Knowledge Among College Students Based on Self-Reported Survey Responses (N=1,131)

Sex Major User n (%) x̅ a

No 113 (77) 6.62 + 3.75 Non-Health Related Yes 33 (23) 10.12 + 3.0 Total 146 (100.0) 7.41 + 4.65 No 60 (91) 8.40 + 4.72 Male Health Related Yes 6 (9) 11.17 + 3.4 Total 66 (100.0) 8.65 + 4.67 No 173 (81.6) 7.24 + 4.8 Total Yes 39 (18.4) 10.28 + 3.1 Total 212 (100.0) 7.80 + 4.68 No 454 (83) 7.18 + 4.2 Non-Health Related Yes 93 (17) 9.24 + 3.88 Total 547 (100.0) 7.53 + 4.22 No 299 (80.4) 8.36 + 4.35 Female Health Related Yes 73 (19.6) 10.30 + 3.79 Total 372 (100.0) 8.74 + 4.3 No 753 (82) 7.65 + 4.3 Total Yes 166 (18) 9.70 + 3.9 Total 919 (100.0) 8.02 + 4.3 No 567 (82) 7.07 + 4.3 Non-Health Related Yes 126 (18) 9.47 + 3.68 Total 693 (61.3) 7.51 + 4.3 No 359 (82) 8.37 + 4.4 Total Health Related Yes 79 (18) 10.37 + 3.8 Total 438 (100.0) 8.73 + 4.4 No 926 (82) 7.57 + 4.4 Total Yes 205 (18) 9.81 + 3.72 Total 1131 (100.0) 7.98 + 4.37 a = mean and standard deviation

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Table 8.

Assessment of Ketogenic Diet Knowledge In-between Interaction Effects Among College Students Based on Self-Reported Survey Responses (N=1,131)

In-Between Effects df Mean Square F Sig.

Sex 1 5.92 0.32 p<0.56

Health Related Major 1 101.91 5.56 p<0.018*

Users 1 416.84 23.1 p<0.001*

Sex* Health Related Major 1 1.33 0.07 p<0.786

Sex* Users 1 20.55 1.14 p<0.286

Health Related Major* Users 1 2.88 0.16 p<0.690

Sex* Health Related Major* Users 1 1.51 0.08 p<0.722

Error 1123 18.03

* statistically significant at p < 0.05

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Table 9.

Assessment of Ketogenic Diet Knowledge by Question Among College Students Based on Self-Reported Survey Responses (N=1,131)

Health % Question Sex Related User na Correct Major Yes 2 33.3 Yes No 15 25.0 Q1 Male Yes 13 39.4 The ketogenic diet was originally No No 30 26.5 developed as a therapeutic treatment Yes 25 34.2 for individuals suffering from epilepsy Yes No 97 32.4 Female Yes 31 33.3 No No 129 28.4 Yes 1 16.7 Yes No 26 43.3 Male Q2 Yes 22 66.7 No The ketogenic diet is a high-fat, high- No 38 33.6 protein, moderate-carbohydrate diet Yes 35 47.9 Yes No 87 29.1 Female Yes 44 47.3 No No 131 28.9 Yes 6 100.0 Yes No 42 70.0 Male Q3 Yes 28 84.8 No The ketogenic diet aims to force the No 65 57.5 body to use ketone bodies as a fuel Yes 60 82.2 Yes source instead of glucose No 223 74.6 Female Yes 71 76.3 No No 289 63.7 Yes 5 83.3 Yes No 31 51.7 Male Yes 18 54.5 Q4 No No 49 43.4 Limiting consumption of carbohydrates Yes 41 56.2 decreases overall carbohydrate stores Yes No 151 50.5 in the body Female Yes 46 49.5 No No 176 38.8 Yes 2 33.3 Yes No 21 35.0 Male Yes 14 42.4 No Q5 No 38 33.6 Carbohydrates are the main dietary Yes 27 37.0 Yes source converted into ketone bodies No 109 36.5 Female Yes 39 41.9 No No 120 26.4

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(Table 9 Continued)

Health % Question Sex Related User na Correct Major Yes 5 83.3 Yes No 36 60.0 Male Q6 Yes 16 48.5 No The ketogenic diet increases fatty acid No 47 41.6 oxidation and utilization Yes 44 60.3 Yes No 144 48.2 Female Yes 45 48.4 No No 187 41.2 Yes 6 100 Yes Q7 No 45 75.0 Male Being in a metabolic state of ketosis Yes 24 72.7 No means a person is utilizing ketone No 61 54.0 bodies as a primary fuel source Yes 57 78.1 Yes No 207 69.2 Female Yes 70 75.3 No No 243 53.5 Yes 3 50 Yes No 16 26.7 Male Yes 11 33.3 Q8 No No 11 9.7 The brain can only use glucose and Yes 23 31.5 ketone bodies as an energy fuel source Yes No 66 22.7 Female Yes 27 29 No No 67 14.8 Yes 4 66.7 Yes No 38 63.3 Male Yes 18 54.5 Q9 No No 47 41.6 Ketone bodies are utilized as a fuel Yes 43 58.9 source in extreme cases of fasting Yes No 175 58.5 Female Yes 56 60.2 No No 196 43.2 Yes 5 83.3 Yes No 38 63.3 Q10 Male Yes 17 51.5 The ketogenic diet aims to mimic a No No 50 44.2 fasted metabolic state without calorie Yes 49 67.1 restriction Yes No 184 61.5 Female Yes 61 65.6 No No 248 54.6

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(Table 9 Continued)

Health % Question Sex Related User na Correct Major Yes 3 50.0 Yes No 30 50.0 Q11 Male Yes 24 72.7 The type of fat (i.e. saturated, No No 48 42.5 monounsaturated, polyunsaturated and Yes 44 60.3 trans fats) consumed on the ketogenic Yes No 146 48.8 diet does not matter Female Yes 54 58.1 No No 218 49.0 Yes 4 66.7 Yes No 23 38.3 Male Yes 22 66.7 Q12 No No 47 41.6 There are many variations of the Yes 39 53.4 ketogenic diet Yes No 126 42.1 Female Yes 51 54.8 No No 195 43.0 Yes 4 66.7 Yes No 26 43.3 Male Q13 Yes 24 72.7 No The ketogenic diet helps to improve No 39 34.5 hunger cues (makes you feel fuller and Yes 47 64.4 Yes less hungry) No 130 43.5 Female Yes 54 58.1 No No 196 43.2 Yes 5 83.3 Yes No 33 55.0 Male Q14 Yes 25 75.8 No The ketogenic diet does not induce No 55 48.70 weight loss Yes 64 87.7 Yes No 190 63.5 Female Yes 74 79.6 No No 278 61.2 Yes 2 33.3 Yes No 18 30.0 Male Yes 18 54.5 Q15 No No 30 26.5 The ketogenic diet does not help to Yes 41 56.2 improve blood sugar levels Yes No 91 30.4 Female Yes 37 39.8 No No 124 27.3

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(Table 9 Continued)

Health % Question Sex Related User na Correct Major Yes 4 66.7 Yes No 18 30 Q16 Male Yes 10 30.3 The ketogenic diet helps with blood No No 21 18.6 cholesterol control (increases HDL- Yes 34 46.6 cholesterol and lowers LDL- Yes No 82 27.4 cholesterol) Female Yes 31 33.3 No No 112 24.7 Yes 1 16.7 Yes No 10 16.7 Male Q17 Yes 4 12.1 No Nutritional ketosis is when ketone No 16 14.2 body concentration is between 1-3 Yes 20 27.4 Yes mmol/dL in the blood No 45 15.1 Female Yes 14 15.1 No No 54 11.7 Yes 3 50.0 Yes No 17 28.3 Male Yes 12 36.4 Q18 No No 27 23.9 The ketogenic diet does not cause an Yes 36 49.3 upset stomach, nausea, or vomiting Yes No 110 36.8 Female Yes 32 34.4 No No 146 32.2 Yes 2 33.3 Yes No 21 35.0 Male Yes 14 42.4 Q19 No No 29 25.7 There are extensive long-term studies Yes 23 31.5 about the ketogenic diet Yes No 138 46.2 Female Yes 22 23.7 No No 153 33.7 a = total responses may differ do to incomplete survey responses

Analysis of Ketogenic Diet Perception Among All College Students

This section focuses on the overall mean perception score of the KD in all students. There was a total of nine questions in this section. Students were asked to answer questions based on a 5-point Likert scale, where a response of (1) meant strongly disagree and a response of (5) meant strongly agree. The higher the score (or

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the closer to 5) the ‘more favorable’ the student’s perception, the lower the score (the closer to 1) the ‘less favorable’ the student’s perception of the KD. The overall mean score suggested students had below average perception of the KD.

Table 10 displays the mean KD perception scores of the among all groups.

User’ (those who answered ‘no I do not currently follow nor have I ever used the ketogenic diet’). Only female (n= 887) and male (n=209) responses were included in the total count, therefore students who responded “other” (n=6) were not included in the final analysis. The overall mean score, 2.85 + 0.54, suggested students on average had lower perception scores of the KD.

Table 11 displays the mean KD perception in-between interaction effect among college students within all groups. Overall, results showed that males on average had significantly higher perception scores versus females (p=0.001) and users had significantly higher perceptions scores versus non-users(p=0.001).

Additionally, there was a significant two-way interaction between sex and major

(p=0.027) and a significant three-way interaction among all independent variables (i.e., sex, health related major, and users) (p=0.026). Within each combination of user group and major, male students had a higher perception of the KD than females, except for

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KD users in non-health related majors, where females had a slightly higher average perception than males.

Table 12 displays the mean KD perception scores by question among college students within all groups. Among all questions, the highest perception score was

4.5+0.5 and the lowest perception score was 1.88+1.0.

Table 10.

Mean Ketogenic Diet Perception Scores Among College Students Based on Self-Reported Survey Responses (N=1,096)

Sex Major User na (%) x̅ b

No 110 (77) 2.97 + 0.54 Non-Health Related Yes 33 (23) 3.13 + 0.65 Total 143 (100.0) 3.01 + 0.57 No 60 (90) 2.88 + 0.51 Male Health Related Yes 6 (9) 3.53 + 0.35 Total 66 (100.0) 2.94 + 0.53 No 170 (81.3) 2.94 + 0.52 Total Yes 39 (18.7) 3.19 + .631 Total 209 (100.0) 2.99 + 0.55 No 429 (82.2) 2.79 + 0.49 Non-Health Related Yes 93 (17.8) 3.17 + 0.57 Total 522 (100.0) 2.86 + 0.53 No 292 (80) 2.70 + 0.51 Female Health Related Yes 73 (20) 2.98 + 0.60 Total 365 100.0) 2.75 + 0.54 No 721 (81) 2.75 + 0.51 Total Yes 166 (19) 3.08 + 0.59 Total 887 (100.0) 2.81 + 0.54 No 539 (81) 2.83 + 0.51 Non-Health Related Yes 126 (19) 3.16 + 0.59 Total 665 (100.0) 2.89 + 0.54 No 352 (82) 2.73 + 0.51 Total Health Related Yes 79 (18) 3.02 + 0.60 Total 431 (100.0) 2.79 + 0.54 No 891 (81.3) 2.79 + 0.51 Total Yes 205 (18.7) 3.11 + 0.60 Total 1096 (100.0) 2.85 + 0.54 a= number of majors may differ du to incomplete responses b = mean and standard deviation

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Table 11.

Assessment of Ketogenic Diet Perception Score In-between Interaction Effects Among College Students Based on Self-Reported Survey Responses (N=1,096)

In-Between Effects df Mean Square F Sig.

Sex 1 3.12 11.4 p <0.001*

Health Related Major 1 0.003 0.01 p <0.919

Users 1 8.56 31.35 p <0.001*

Sex* Health Related Major 1 1.34 4.93 p <0.027*

Sex* Users 1 0.09 0.33 p <0.568

Health Related Major* Users 1 0.63 2.31 p <1.29

Sex* Health Related Major* 1 1.36 4.97 p <0.026* Users

Error 1088 0.27

* statistically significant at p < 0.05

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Table 12.

Assessment of Ketogenic Diet Perception Scores by Question Among College Students Based on Self- Reported Survey Responses (N=1,096)

Health Question Sex related User na x̅ Major Yes 6 4.50+0.5 Yes No 60 4.25+0.7 Male Q1 Yes 33 4.06+0.1 No I believe the ketogenic diet is a popular No 112 3.96+0.8 weight loss method used today Yes 73 4.23+1.0 Yes No 299 4.19+0.1 Female Yes 93 4.46+0.6 No No 450 4.18+0.8 Yes 6 3.83+0.9 Yes No 60 2.58+1.3 Male Q2 Yes 33 2.64+1.4 No I believe following the ketogenic diet No 112 2.90+1.1 guarantees weight loss Yes 73 3.22+1.2 Yes No 298 2.56+1.1 Female Yes 93 3.35+1.0 No No 449 2.74+1.1 Yes 6 3.33+1.2 Yes No 60 2.65+.10 Male Q3 Yes 33 3.18++.3 No I believe the ketogenic diet No 111 2.75 +1.0 recommendations are too high in fat Yes 73 2.73+1.1 Yes and not enough in protein and No 295 2.35+0.9 Female carbohydrates Yes 93 2.86+1.1 No No 440 2.51+0.9 Yes 6 4.33+0.8 Yes No 59 2.85+1.1 Male Yes 33 3.33+1.0 No Q4 No 112 2.96+1.0 I believe the ketogenic diet has health Yes 73 2.90+1.2 Yes benefits that outweigh health risks No 295 2.39+1.0 Female Yes 93 3.29+1.1 No No 441 2.66+1.1 Yes 6 2.50+1.4 Yes No 60 2.58+1.1 Male Q5 Yes 33 2.94+1.4 No I believe the ketogenic diet is easy to No 110 2.86+1.1 follow Yes 73 2.70+1.3 Yes No 294 2.59+1.1 Female Yes 93 3.08+1.2 No No 440 2.44+1.1

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(Table 12 Continued)

Health Question Sex related User na x̅ Major Yes 6 3.33+1.0 Yes No 60 2.30+1.2 Male Q6 Yes 33 2.55+1.1 No I believe the ketogenic diet is safe No 110 2.34+1.1 enough for someone to follow for the Yes 73 2.27+1.3 Yes rest of his/her life No 294 1.88+1.0 Female Yes 93 2.71+1.3 No No 439 2.02+1.1 Yes 6 3.83+1.0 Yes No 60 3.60+1.2 Male Q7 Yes 33 3.30+1.3 No I believe the ketogenic diet should only No 110 3.65+1.0 be recommended to individuals by a Yes 73 3.52+1.2 Yes physician under supervision No 292 4.00+1.1 Female Yes 93 3.09+1.5 No No 432 3.92+1.0 Yes 6 3.50+0.5 Yes No 60 2.73+1.0 Q8 Male Yes 33 3.48+1.0 I believe the ketogenic diet is No No 110 2.89+0.9 dangerous (i.e increases a person's risk Yes 73 2.90+1.2 of developing diseases such as Yes No 292 2.39+1.0 cardiovascular disease, etc.) Female Yes 93 3.15+1.1 No No 431 2.55+0.1 Yes 6 2.67+1.0 Yes No 60 2.43+1.0 Q9 Male Yes 33 3.48+1.0 I believe the ketogenic diet puts people No No 110 2.51+1.0 at risk for nutrient Yes 73 2.38+1.1 deficiencies Yes Female No 290 1.93+0.8 No Yes 93 2.55+1.1 a = total responses may differ do to incomplete survey responses

Discussion

The purpose of this study was to examine student’s knowledge, perception, and usage of the ketogenic diet. The study results indicated: 1.) there was a significant difference in the knowledge of the ketogenic diet between health related and non-health

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related majors, therefore Hypothesis 1 was accepted 2.) there was no significant difference in the knowledge of the ketogenic diet between sexes, therefore Hypothesis 2 was rejected 3.) there was a significant difference in the knowledge of the ketogenic diet among users and non-users, therefore Hypotheses 3 was accepted 4.) there was no significant difference in the perception of the ketogenic diet between health related and non-health related majors, therefore Hypothesis 4 was rejected 5.) there was a significant difference in the perception of the ketogenic diet between sexes, therefore

Hypothesis 5 was accepted 6.) there was a significant difference in the perception of the ketogenic diet among users and non-users therefore Hypotheses 6 was accepted.

Ketogenic Diet Use Among College Students

The escalating overweight/obesity epidemic is a significant public health concern and has been associated with increased risks for type 2 diabetes (T2DM), cardiovascular disease (CVD), hypertension (HTN), cancer, arthritis, as well as other negative health outcomes (Marcia, 2018; Schwartz, 2014). This ongoing rise of obesity in the U.S. proposes undeniable health risks for every population, especially college students

(Fedewa et al., 2014). One method college students’ utilize in order to improve their weight status are FD. While research shows successful weight management plans combine diet, exercise and behavioral therapy, students turn to FD such as the KD, in hopes of achieving rapid weight loss (The Academy of Nutrition and Dietetics, 2017;

Swanson 2015). It’s important to note that the KD was not originally developed as a weight management method. In fact, the KD was originally developed as a treatment method for patients suffering from epilepsy and other seizure-related disorders to reduce

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seizure episodes (The Academy of Nutrition and Dietetics, 2017). For these patients, the

KD strict nutrition recommendations (which significantly reduces overall carbohydrate intake) are difficult for patients to adhere to long-term (Bonnie et al., 2003). This research is concerning because as the KD continues to gain popularity for weight management, students may also struggle with adhering to KD recommendations long- term. Therefore, students utilizing the KD as a FD may be at higher risk for developing metabolic complications associated with FD use or ‘yo-yo; dieting (Obert et al. 2017;

Abbasi, 2018).

The results of the current study showed approximately 30% of students responded to have using a FD. This result is reported quite similarly in other studies that show a 34% FD usage among other college student populations (Pedtke, 2001).

Overall, 18.1% of students reported involvement with the KD. Although there are multiple other studies analyzing KD use, most studies focus on KD use for chronic disease treatment and prevention, not weight management or weight loss (Cicero et al.,

2015; Hussian et al., 2012). Therefore, this current study provides researchers with some insight regarding KD use among college students for weight management.

KD users (N=205) were asked two additional questions pertaining to their most current involvement with the KD: the duration (how long they have been or how long they did follow) and outcome (or result). For duration, students could select: ‘less than a week’, ‘1-4 weeks’, ‘5-12 weeks (3 months)’, ‘13-26 weeks (6 months)’, or ‘more than 26 weeks (6 months+)’. Results indicated about two-thirds (>65%) of users have been following or followed the KD for a month of less and only a small number of

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users (5%) responded to using the KD for more than 26 weeks (6+ months). These results show more than half of students stayed on a FD for a month or less and therefore back current research that suggests FD such as KD, are not effective weight management methods for college students long-term (Greaney et al., 2009; Pedtke,

2001). One reason why FDs, such as the KD, are difficult to follow long-term is because of the extreme dietary restrictions immediate required of users . Such recommendations could require extreme calorie and food restrictions, and rigorous exercise; two challenging expectations for most individuals to follow long-term (Bacon & Aphramor,

2011; Anderson et al., 2001; Crosser, 1985).

KD users were also asked about their outcome (or result) following the KD. KD users could answer: ‘weight loss and kept weight off’, weight loss but gained weight back’, ‘no change’ or ‘other’. About 20% of users responded to ‘weight loss and kept it off’, more than one-third (38%) of users responded, ‘weight loss but gained it back’, and almost half (42%) of users responded, ‘no change’. Of the users that selected

‘other’ one student responded, ‘gained weight’ and another student responded, ‘lost weight and only gained some back’. Overall these results suggest that majority of students saw no change when utilizing the KD. This outcome reflects past studies suggesting the KD is not sustainable long-term (The Acadamey of Nutrition and

Dietetics, 2017; Bonnier et al., 2013).

Ketogenic Diet Knowledge Among College Students

The results of the current investigation showed that overall knowledge scores of the KD were significantly higher among health related majors and users versus non-

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health related majors and non-users. One potential reason why health related majors had higher knowledge scores is because although health related majors course requirements greatly vary, such students are required to engage in more health and science courses (i.e., biology, chemistry, physiology, body metabolism, personal health, nutrition, etc.) than non-health related majors. Therefore, it would be appropriate to assume that such students would be more knowledgeable about FD, such as the KD, because of their increased exposure to health and nutrition related information (The

American Dietetic Association, 2006).

A possible reason why users had higher knowledge scores then non-users is because if one becomes interested in a particular topic such as diet or weight loss, research shows those individuals are more likely to investigate information pertaining to that topic; increasing their overall knowledge and awareness of the subject (Connor-

Greene PA, 1988; Greaney et al., 2009; Yahia et al, 2016). Therefore, users may have an increased knowledge of the KD versus non-users because of their personal interests to learn more about it (Poobalan, Aucott, Clarke and Smith, 2014). Although results were considered significant among both groups, mean KD knowledge sores among major and user groups were below average, answering less than half of all knowledge questions correctly. Thus, the true significance of this finding suggests a poor overall knowledge of the KD among students. This result could be a reflection of the non- credible KD resources students may be using for KD information.

Overall, male, health related majors’ users (N=6) seemed to have the highest overall knowledge score. In addition, this was the only group where every participant

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correctly answered at least one of the questions provided (100% for questions 3 & 7).

Among both sexes, non-health related majors and non-users had the lowest mean knowledge scores of all groups and were responsible for two of the lowest scoring knowledge questions (questions 8 & 17), 9.7% and 11.7% respectively. These results coincide with other studies that suggest students with frequent health and nutrition exposure and who express interest in health and nutrition, are likely be more knowledgably of diet and weight loss methods such as the KD (The American Dietetic

Association, 2006). Furthermore, these students may feel confident with administering diet regimens such as the KD on their own because of their heightened diet awareness

(Connor-Greene PA, 1988, Greaney et al., 2009; Poobalan, Aucott, Clarke and Smith,

2014).

Overall, students seemed to struggle with identifying the correct blood ketone body (KB) for nutritional ketosis (question 17). The purpose of the KD, is by restricting carbohydrate intake and increasing fat intake, the body is forced to enter a state of nutritional ketosis, where fat becomes the primary fuel source over carbohydrate (Gropper & Smith, 2013). Blood ketone body concentration is the most accurate measurement when testing for nutritional ketosis. The current study results suggest all students, have a poor understanding of ketosis biomarkers. This result proposes a disconnect between KD users perceived usage of the KD versus they’re actual usage of the KD.

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Ketogenic Diet Perception Among College Students

The results showed that overall perception scores of the KD were significantly higher or more ‘favorable’ among males and users versus females and non-users.

Overall, the study showed that on average, health related major groups, and non-health related non-users, who were males, had the highest perception scores among all groups.

These findings show that for males, higher perception scores were significantly affected by health related major and non-user groups. Among females, non-health related majors who were users had the strongest feelings towards the KD. These findings show that for females, higher perception scores were significantly impacted by major type and user groups. Overall, females within both major groups, who were non-users, were not in favor of the KD, with the lowest mean perception scores of, 2.70 + 0.5 (health related) and 2.79 + 0.49 (non-health related). Among these groups, female, health related, non-users, were responsible for two of the lowest scoring perception questions

(question 6 & 9), 1.88 + 1.0 and 1.93 + 0.8 respectively. This data suggests female, health related non-users (1) do not believe that the KD is safe enough for someone to follow for the long-term (2) believe the KD does not put individuals at risk for nutrient deficiencies.

Overall, male, health related majors, who were users, seemed to be most in favor of the KD, scoring the highest (3.53 + 0.35) among all students in this section.

Although this result was considered significant, even this group conveyed an overall neutral perception of the KD. Thus, the true significance of this result suggested an overall neutral feeling towards the KD among students. Male, health related majors,

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who were users, were also responsible for the highest scoring question (4.5 + 0.5 for question 1), which stated, ‘I believe the ketogenic diet is a popular weight loss method used today.’ This result shows overall, students agree that the KD is a frequently chosen weight management method utilized today. This outcome supports current research, that college students are aware of their overweight and obesity risk and are taking an initiative to become more health conscious by shifting their attention to weight loss and weight management methods. (Wing, 2003).

Limitations

A potential limitation of this study is the survey questionnaire was self-reported, thus responses may be dishonest. The survey was sent to students via email and could be taken on any smart device (computer, smart-phone, tablet etc.) therefore, students could have discussed answers among one another, potentially skewing their responses. Outside influences may have discouraged students from disclosing information about their experiences with the KD given the surveys ‘take home’ flexibility. In addition, the survey questionnaire concentrated on questions pertaining to the KD and weight management. Therefore, questions were limited and did not reflect knowledge of other possible KD topics (cognitive effects, other chronic disease, epilepsy etc.).

Application

Despite the limitations, this study provides further information about KD knowledge, perception, and usage among college students. This current study showed

30% of students had tried a FD, while 18.1% admitted to using the KD. These results indicate some students are engaging in FD such as the KD. Such results are concerning

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considering the lack of knowledge represented by this population. With this evidence, future research should be conducted to examine the knowledge and perception of other

FD in similar college populations so comparisons can be made between their perceived knowledge and actual knowledge of the FD. In addition, further investigations should be conducted addressing the long-term outcomes of students utilizing KD for weight management to counterbalance the lack of studies analyzing the use of the KD and other

FD within this population.

Conclusion

KD use is prevalent among college students. All students demonstrated below average KD knowledge and perception scores. These findings suggest that college students perceived KD effectiveness as favorable among both male user groups, except for female non-health related users where perception scores were higher. This indicates that knowledge and perception of the KD is inconsistent among male college students and is unlikely to impact KD use due to other influences such as lifestyle behaviors and beliefs that are more likely to determine involvement with the KD.

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APPENDICES

APPEXDIX A

HEALTH RELATED MAJOR DESCRIPTION

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Appendix A

Health Related Major Description

Health Related College Majors By College:

College of Arts and Sciences -Biological Sciences (cell biology and molecular genetics, ecology and evolutionary biology, integrative physiology and neurobiology, biology) -Chemistry (all chemistry including biochemistry) -Biomedical Sciences (neuroscience, physiology, pharmacology, clinical psychology, clinical epidemiology) -Medical Anthropology -Pre-Med -Pre-Pharmacy -Physical Science -Physics -Physiological Sciences

College of Education, Health, and Human Services -Clinical Mental Health Counseling -Educational Sciences (life science, life science/chemistry) -Exercise Science -Exercise Physiology -Health Education and Promotion -Health Sciences -Hospitality Management -Human Development and Family Studies -Human Sexuality -Integrated Health Studies -Lifespan Development -Nutrition

-Sports Medicine

College of Nursing -Nursing

College of Podiatric Medicine -Pediatrics

College of Public Health -Public Health (all concentrations)

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APPENDIX B

CONSENT FORM

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Appendix B

Consent Form

Knowledge and Perception of the Ketogenic Diet in College Students at a Midwestern University

Thank you for your interest in taking this online questionnaire. Before taking part in this study, please read the consent form below and click on the "I Agree" button at the bottom of the page if you understand the statements and freely consent to participate in the study.

Consent Form

This study involves a web-based questionnaire designed to understand how college students perceive the use of the ketogenic diet or weight loss and weight management. This study is being conducted by Professor Eun-Jeong Ha, an associate professor of Nutrition & Dietetics, and Alexandria D’Agostino, a graduate student in Nutrition & Dietetics. The Kent State University Institutional Review Board has approved this study. No deception is involved, and the study involves no more than minimal risk to participants (i.e., the level of risk encountered in daily life).

Participation in the study typically takes around 15 minutes and is strictly anonymous. Participants begin by answering a series of demographic questions. Next, students will be asked general questions about their weight loss experiences. Following this section, students will answer knowledge questions about the ketogenic diet to the best of their ability. The last section will ask perception questions and measure how students feel about the ketogenic diet.

All responses are treated as confidential, and in no case will responses from individual participants be identified. Rather, all data will be pooled and published in aggregate form only. Participants should be aware, however, that the experiment is not being run from a "secure" https server of the kind typically used to handle credit card transactions, so there is a small possibility that responses could be viewed by unauthorized third parties (e.g., computer hackers).

No adverse reactions have been reported thus far during the completion of this questionnaire. Participants will be given the option of entering a raffle for a $25 Amazon e-gift cards. Contact information obtained for the gift card raffle will not in any way be linked to responses from the questionnaire. Participation is voluntary. Refusal to take part in the study involves no penalty or loss of benefits to which participants are otherwise entitled, and participants may withdraw from the study at any time without penalty or loss of benefits to which they are otherwise entitled.

If participants have further questions about this study or their rights, or if they wish to lodge a complaint or concern, they may contact the principal investigator, Professor Eun-Jeong Ha, at (330) 672-2701; or the Kent State University Institutional Review Board, at (330) 672-2704. If you are 18 years of age or older, understand the statements above, and freely consent to participate in the study, click on the "I Agree" button to begin the survey.

APPENDIX C

SURVEY QUESTIONNAIRE

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Appendix C

Survey Questionnaire

Demographic Questions

1. What is your sex?

-Male -Female -Other (please specify)

2. What is your age in years?

-Please Specify

3. What is your ethnicity?

-White/Caucasian -Black/African American -Hispanic/Latino -Asian/Pacific Islander -Middle Eastern -Native American/American Indian -Other (please specify)

4. What is your current height (please specify in feet and inches)

-Please Specify Feet (between 3-7) -Please Specify Inches (between 0-11)

5. What is your current weight? (please specify in pounds = lbs)

-Please Specify

6. What is your current class standing?

-Freshman -Sophomore -Junior -Senior

-Graduate student – Masters Level -Graduate student – Doctoral Level

7. What is your college major at Kent State University?

-Please Specify

8. Have you ever taken a college level nutrition course?

-Yes -No -Unsure (please specify)

9. What are your current living arrangements?

-On campus -Off campus apartment/renting alone -Off campus apartment/renting with significant other -Off campus apartment/renting with roommate -Commuter living with parents -Other (please specify)

General Questions

10. Have you ever tried a fad diet? (a short-term weight loss method such as the cabbage diet, detox diet, etc.)?

-Yes -No

11. Have you ever heard of the ketogenic diet? (If not, please end survey)

-Yes -No

12. Do you currently follow the ketogenic diet? (if you have never tried it, skip to question 15)

-Yes -Currently no, but I have before -No

13. In response to question 12, how long have you been following/ how long did you follow the ketogenic diet?

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-Less than a week -1-4 weeks (1 month) -5-12 weeks (3 months) -13-26 weeks (6 months) -More than 26 weeks (6+ months) -I don’t know

14. What was your result following the ketogenic diet? (please answer according to your latest trial)

-Weight loss and kept weight off -Weight loss, but gained weight back -No change -Other (please specify)

Knowledge Questions

The following questions are designed to assess your knowledge of the ketogenic diet. All questions are in true or false format. Please read each question carefully. If you do not understand or do not feel comfortable answering a question, please select "I don't know." Please do not guess if you do not know the answer. All the correct answers to these questions will be provided at the end of the survey.

15. The ketogenic diet was originally developed as a therapeutic treatment for individuals suffering from epilepsy.

-True -False -I don’t know

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16. The ketogenic diet is a high-fat, high-protein, moderate-carbohydrate diet.

-True -False -I don’t know

17. The ketogenic diet aims to force the body to use ketone bodies as a fuel source instead of glucose

-True -False -I don’t know

18. Carbohydrates are the main dietary source converted into ketone bodies.

-True -False -I don’t know

19. The ketogenic diet increases fatty acid oxidation and utilization.

-True -False -I don’t know

20. Being in a metabolic state of ketosis means a person is utilizing ketone bodies as a primary fuel source.

-True -False -I don’t know

21. The brain can only use glucose and ketone bodies as an energy fuel source.

-True -False -I don’t know

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22. Ketone bodies are utilized as a fuel source in extreme cases of fasting.

-True -False -I don’t know

23. The ketogenic diet aims to mimic a fasted metabolic state without calorie restriction.

-True -False -I don’t know

24. The type of fat (i.e. saturated, monounsaturated, polyunsaturated and trans fats) consumed on the ketogenic diet does not matter.

-True -False -I don’t know

25. There are many variations of the ketogenic diet.

-True -False -I don’t know

26. The ketogenic diet helps to improve hunger cues (makes you feel fuller and less hungry).

-True -False -I don’t know

27. The ketogenic diet does not induce weight loss.

-True -False -I don’t know

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28. The ketogenic diet does not help to improve blood sugar levels.

-True -False -I don’t know

29. The ketogenic diet helps with blood cholesterol control (increases HDL-cholesterol and lowers LDL-cholesterol).

-True -False -I don’t know

30. Nutritional ketosis is when ketone body concentration is between 1-3 mmol/dL in the blood.

-True -False -I don’t know

31. The ketogenic diet does not cause an upset stomach, nausea, or vomiting.

-True -False -I don’t know

32. There are extensive long-term studies about the ketogenic diet.

-True -False -I don’t know

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Perception Questions

The following questions are designed to understand how you think about the ketogenic diet. Please ready the questions carefully. Once you have read the question, please select one of the five options below based on how strongly you agree or disagree with the statement provided.

33. I believe the ketogenic diet is a popular weight loss method used today.