Determination of the Total Dietary Polyphenol Load of a Population of Healthy Adults in Appalachia, Ohio A thesis for oral defense presented to the faculty of the College of Health Sciences and Professions of Ohio University In partial fulfillment of the requirements for the degree Master of Science Mary J. Connell April 2021 © 2021 Mary J. Connell. All Rights Reserved. 2 This thesis titled Determination of the Total Dietary Polyphenol Load of a Population of Healthy Adults in Appalachia, Ohio by MARY J. CONNELL has been approved for the School of Applied Health Sciences and Wellness and the College of Health Sciences and Professions by Robert Brannan Professor of Applied Health Sciences and Wellness John McCarthy Interim Dean, College of Health Sciences and Professions 3 Abstract CONNELL, MARY, M.S., April 2021, Food and Nutrition Sciences Determination of the Total Dietary Polyphenol Load of a Population of Healthy Adults in Appalachia, Ohio Director of Research: Angela Hillman Director of Thesis: Robert Brannan Interest in dietary polyphenols has dramatically increased in recent years. This is because these secondary plant metabolites have been shown to have anti-oxidant and pre- biotic qualities (Marchesi et al., 2016). A polyphenol is classified as a compound that contains an aromatic ring and hydroxyl group, and nearly all polyphenols have been implicated with positive health benefits such as disease prevention and treatment (Pandey & Rizvi, 2009). This may be largely due to the impact of polyphenols on the gut microbiome. Certain strands of bacteria are thought to feed off these colorful compounds. Researchers have suggested that individuals who frequently consume large amounts of polyphenols are more likely to have a diverse array of healthy bacteria present in their gut microbiomes. Many commonly consumed health products such as tea, berries, cocoa, and red wine are high in polyphenols. The current research in polyphenols has led to a rise in popularity of certain polyphenol food supplements. Tart cherry juice and powder have become particularly widespread dietary enhancers. Although these products have some potent potential health benefits, consuming polyphenols through natural food sources is thought to be a more effective way to consume a large and diverse quantity of these antioxidant-like nutrients. However, literature that quantifies total dietary polyphenol 4 load of diets is limited. The goal of this project is to analyze 3-day diet logs to calculate the total polyphenol load of participants from the Athens, Ohio area. Logs will be analyzed to determine if there is a significant difference in total polyphenol load between participants supplementing with tart cherry juice, participants supplementing with tart cherry powder, and participants who are not supplementing with a tart cherry product. 5 Dedication Dedicated to the memory of my Grandpa Robarge, who was a great example of how to use knowledge and wisdom to care for others. And to my family, who have supported and encouraged me in my pursuits and made this thesis possible. 6 Acknowledgments I would like to thank everyone who has provided me with the resources and guidance to complete this project. Thank you to Dr. Angela Hillman, for providing me with insight and direction as I have worked through the research and writing process. Thank you to Dr. Brannan, for directing me to this project and helping me navigate deadlines and formatting. Thank you to Dr. Deborah Murray for her support and suggestions as she served on my committee. Thank you to the teachers, students, and members of the Food and Nutrition Sciences community at Ohio University. I am so grateful to have had the opportunity to complete this program and learn from such exceptional and experienced people. 7 Table of Contents Page Abstract ............................................................................................................................... 3 Dedication ........................................................................................................................... 5 Acknowledgments............................................................................................................... 6 List of Tables ...................................................................................................................... 9 List of Figures ................................................................................................................... 10 Chapter 1: Introduction ..................................................................................................... 11 Background ................................................................................................................. 11 Statement of the Problem ............................................................................................ 13 Research Questions ..................................................................................................... 13 Hypothesis................................................................................................................... 14 Purpose and Significance ............................................................................................ 14 Delimitations ............................................................................................................... 15 Limitations .................................................................................................................. 15 Definitions................................................................................................................... 16 Abbreviations .............................................................................................................. 17 Chapter 2 ........................................................................................................................... 18 Polyphenol Classification ........................................................................................... 18 Flavonoids ................................................................................................................... 18 Non-flavonoids ........................................................................................................... 22 Factors that Influence Polyphenol Content of Foods .................................................. 23 Common Polyphenol Sources ..................................................................................... 25 The Biology of Polyphenols ....................................................................................... 28 Previous Research ....................................................................................................... 34 Chapter 3: Methodology ................................................................................................... 39 Recruitment ................................................................................................................. 39 Supplementation Protocol ........................................................................................... 39 Diet Tracking .............................................................................................................. 41 Analysis....................................................................................................................... 41 Chapter 4: Results ............................................................................................................. 43 Chapter 5: Discussion ....................................................................................................... 46 8 Conclusion ........................................................................................................................ 50 References ......................................................................................................................... 51 Appendix A: Example Polyphenol Estimation ................................................................. 84 Appendix B: List of Excluded Foods................................................................................ 86 Appendix C: List of Polyphenol Content of Foods from Literature ................................. 87 9 List of Tables Page Table 1 Studies on Polyphenol Intake of Various Populations........................................ 37 Table 2 Supplemental Nutrition Information ................................................................... 40 Table 3 Descriptives of Groups ....................................................................................... 44 10 List of Figures Page Figure 1 Polyphenol Structures and Examples ................................................................ 11 Figure 2 Polyphenol Absorption and Metabolism .......................................................... 33 11 Chapter 1: Introduction Background Polyphenols are a naturally occurring organic molecules that contain at least one aromatic ring and attached hydroxyl group (Rasouli et al., 2017). Polyphenols are divided into categories based on how many aromatic rings they contain and how these rings are structurally connected. Examples are shown in Figure 1. Figure 1 Polyphenol Structures and Examples From “Plant Polyphenols as Dietary Antioxidants in Human Health and Disease,” by K.B. Pandey & S.I. Rizvi, 2009, Oxidative Medicine and Cellular Longevity, 2(5), 270– 278. doi: 10.4161/oxim.2.5.9498. CC by 3.0. 12 These secondary metabolites are present in plants and consumption of these diverse compounds has been implicated in the prevention of