Ruminococcaceae Genus Bacteroides Anaerotruncus Species B

Cultivating Changing Gut Microbial Communities

Lauri O. Byerley, RDN, LDN, FAND Associate Professor Louisiana State University Health Sciences Center Department of Physiology Disclaimer

Research Funding Through the Years: • NCI • NIAAA • US Army • American Institute of Cancer Research • California Walnut Commission • American Public University • Louisiana State University Health Sciences Center

Hippocrates….”All Diseases begin in the gut” Collaborators:

DAVID WELSH CHRISTOPHER TAYLOR BRITTANY LORENZO SHELIA BANKS MENG LUO MONICA PONDER (VIRGINIA TECH) EUGENE BLANCHARD Seminar Layout • Learning objectives • Definition of terms • Introduction • Microbe view of the gut • Why cultivating microbes is important • Detecting gut microbes • Feeding our gut microbes • Proof of concept – Can we cultivate specific microbes? • Summary Learning Objectives • Diagram the GI tract from a microbe’s perspective • Describe why we should cultivate gut microbes • Explain the process by which microbes are detected • Produce a list of several different fiber types and several foods/ingredients associated with each fiber type • Describe alterations in gut microbiota following dietary changes • List the most appropriate foods to cultivate our gut microbiome Definition of Terms

• Microbiota – a collection or community of microbes. Includes bacteria, fungi, archaea and viruses • Microbiome – refers to the genomes of all the microbes in a community • Metagenomics ‐ a technique that reveals biological functions of an entire community • Metabolomics – measurement of metabolites

https://media.npr.org/assets/img/2016/08 /09/e‐coli_wide‐ b2909f1ef2e257a4c5fa01112174ab941c24 7871‐s800‐c85.jpg Introduction

• We are more bacteria than human… • More bacteria in and on our body than human cells • Healthy human has approximately 40 trillion bacteria in gut • 500 to 1,000 species encompassing 10,000 strains • Humans – 23,000 genes • Microbiome – estimated 3,300,000 genes (150 fold more) • Mutual relationship

http://www.global‐engage.com/wp‐content/uploads/2017/04/human‐microbiome‐NGS.jpg Microbiome – “Human Organ”

• Weight ‐ approximately 1‐2 kg • No distinct structure ‐ organized system of cells like the immune system • Each person has a unique microbiome • So unique we may be able to track forensically http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1500832/ Microbes view of our gut • Major barriers for microbes entering the gut: • low pH • Saliva • Bile • Immune system • Finding a place to attach to intestinal wall • Surviving a widely varied diet

https://elearning.kullabs.com/img/note_images/b7nZNAW6sMPqqMTg.jpg

Keep these things in mind when cultivating our gut microbiome Microbial Biomass & pH Figure 1(A) Small intestine mucosal immune system landscape.

M Zaeem Cader, and Arthur Kaser Gut 2013;62:1653-1664 Figure 1(B) Colon (large intestine) mucosal immune system.

M Zaeem Cader, and Arthur Kaser Gut 2013;62:1653-1664 What is happening in the gut?

For those microbes that manage to colonize the gut: • gut flora perform regular tasks of digestion, vitamin production, many others • Gene transfer between the myriad of species in the gut can generate new combinations including ones resistant to drugs “superbugs” https://i2.wp.com/thescientificparent.or g/wp‐content/uploads/2017/03/GI‐ Tract‐Small.png?fit=816%2C971&ssl=1 Why is Cultivating Important?

Many Functions of Our Gut Bacteria

https://www.researchgate.net/profile/Brigitta_Brinkman/publication/281518789/figure/fig1/AS:313058971930624@1451650483890/Main‐functions‐of‐bacteria‐in‐the‐gut‐ Bacteria‐benefit‐the‐host‐in‐many‐ways‐Besides.png Who Are the Players? Scientific Classification or Taxonomic Rank • Don’t get hung up on this – just know it exists • King Play Chess On Fine Green Silk • 3 Kingdoms: • Bacteria • Archaea King Play • Eukaryota Chess Kingdom Bacteria Bacteria On Fine Phylum Bacteriodetes Firmicutes Green Class Bacteriodetes Clostridia Silk Order Bacteriodales Clostridiales Family Bacteroidaceae Ruminococcaceae Genus Bacteroides Anaerotruncus Species B. fragilis A. colihominis Methods

• We cannot grow most bacteria in the lab • We must detect DNA • Fecal samples collected from the descending colon • DNA isolated • V3 hypervariable region of 16S rRNA gene deep sequenced on an Illumina MiSeq. • Data analyzed using the UPARSE and QIIME pipeline and SAS. Species Name LOB1NTBMCA LOB1PFW LOB2PFW None;Other;Other;Other;Other;Other;Other 00 0 k__Bacteria;Other;Other;Other;Other;Other;Other 0.004396 0.001905 0.003637 k__Bacteria;p__Actinobacteria;Other;Other;Other;Other;Other 7.14E‐05 0 0.000222 k__Bacteria;p__Actinobacteria;c__Actinobacteria;o__Actinomycetales;Other;Other;Other 0 0 0 k__Bacteria;p__Actinobacteria;c__Actinobacteria;o__Actinomycetales;f__Actinomycetaceae;g__Actinomyces;Other 0 0 0 k__Bacteria;p__Actinobacteria;c__Actinobacteria;o__Actinomycetales;f__Actinomycetaceae;g__Arcanobacterium;s__ 0 0.000159 0

• Excel spreadsheet with numbers • Use these numbers to determine significant differences

http://learn.genetics.utah.edu/content/microbiome/study/image How to analyze data? s/microbesdoing.jpg Fig. 4 Alpha diversity: species richness (number of taxa) within a single microbial ecosystem. How many different microbial species could be detected in one sample?

Beta diversity: diversity in microbial community between different environments (difference in taxonomic abundance profiles from different samples). How different is the microbial composition in one environment compared to another?

https://www.researchgate.net/profile/Patrice_Cani/publication/2Atherosclerosis 2018 268, 117-126DOI:81288066/figure/fig5/AS:271086130561031@1441643378758/Mice‐Fed‐ (10.1016/j.atherosclerosis.2017.11.023) a‐Lard‐Diet‐Have‐Increased‐Adiposity‐ and‐Distinct‐Gut‐Microbiota‐Composition.png Microbe Communities

• Microbes act in communities • Microbes react to their surroundings • Shift when the environment changes • Change quickly

http://learn.genetics.utah.edu/conte nt/microbiome/intro/images/microb es.jpg Factors Affect Human Gut Microbiome • Age • Activity/Exercise • Emotional State/Stress • Diet • Gender • Climate • Occupation • Hygiene • Antibiotics • Medications • Living with animals • Where you live • Diurnal Variation http://learn.genetics.utah.edu/content/microbiome/changing/images/change6.jpg Diet is a big player for the gut microbiome Diet Influences the Gut Microbiome

• We acquire microbiome at birth • Long‐term diet effects: Bacteroides (Genus) Prevotella (Genus) Diet (Phyla ‐ Bacteriodetes) (Phyla – Baceriodetes) High animal protein, high fat, low High Low carbohydrate (Atkins, Paleo) High carbohydrates, low animal Low High protein, low fat

• Japanese harbor organisms that aids in seaweed digestion • African children – high Bacteroidetes and deplete of Firmicutes to maximize energy uptake from fiber‐rich diet • vegetarians have gut flora that are better equipped to break down plant roughage, making otherwise indigestible molecules such as cellulose available for humans Scientific Evidence – Diet Influences Gut Microbiome

Carnivore Omnivore Hervifore

Meugge BD et al. Science. 2011 May 20; 332(6032): 970–974. Partitioning of People Into Enterotypes

• Difficult studies because increases in one macronutrient typically associated with decrease in another • Higher complex carbohydrate diet – more Prevotella • Higher fat/protein diet – more Bacteroides

Wu GD, et al. Science 334:105, 2011 Macronutrient composition rapidly impacts microbiome

Changes within 24 hours

Wu GD et al. Science. 2011 Oct 7; 334(6052): 105–108. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3368382/ Macronutrient composition rapidly impacts microbiome

Plant‐based Animal‐based Diet Diet

Similarity of each individual’s gut microbiota to their baseline communities (β‐diversity, Jensen‐Shannon distance) decreased on the animal‐based diet (dates with q<0.05 identified with asterisks; Bonferroni‐corrected, two‐sided Mann‐Whitney U test). David, LA Et al Nature. 2014 Jan 23; 505(7484): Community differences were apparent one day after a tracing dye 559–563. showed the animal‐based diet reached the gut (blue arrows depict https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3957 appearance of food dyes added to first and last diet day meals 428/bin/nihms536070f1.jpg Scientific Evidence ‐ Diet Influences Gut Microbiome

16S rRNA gene surveys reveal a clear separation of two children populations investigated. BF = Children from a rural African village of Burkina Faso (BF) Diet is • low in fat and animal protein • rich in starch, fiber, and plant polysaccharides • predominantly vegetarian

EU = European children Diet is • typical western diet high in animal protein, sugar, starch, and fat • low in fiber. Carlotta De Filippo et al. PNAS 2010;107:33:14691-14696

• Changes occur rapidly ‐ within 24 hours of eating a high fat/low fiber or low fat/high fiber diet • Changes are significant • Changes are modest • Changes only last for at least 10 days The adult gut microbiome is characterized as existing in a steady state that requires a major disturbance to permanently alter that Microbiome is strongly associated state. Short-term diet interventions may transiently alter the gut microbiome community with long‐term diet. structure, but long-term diet changes are required to shift to a new steady-state.

Voreades N., Kozil, A, Weir TL. Front Microbiol. 2014; 5: 494. What is our microbes favorite food? Fiber

Dietary Fiber: Non-digestible soluble and insoluble carbohydrates ( > 3 monomeric units), and lignin that are intrinsic and intact in plants; isolated or synthetic non-digestible carbohydrates (> 3 or more monomeric units) determined by FDA to have physiological effects that are beneficial to human health.1 Prebiotic – a substrate that is selectively utilized by host microorganisms conferring a health benefit.2

Probiotic – are live microorganisms that are intended to have health benefits (includes foods (such as yogurt), dietary supplements, and products that aren't used orally, such as skin creams.3 1. U.S. Food & Drug Administration, 26 May 2017 Final ruling on dietary fiber definition 2. Gibson, G. R., et al. (2017). Expert consensus document: The International Scientific Association for Probiotics and Prebiotics https://www.garmaonhealth.com/wp‐ (ISAPP) consensus statement on the definition and scope of prebiotics. Nature Reviews Gastroenterology & Hepatology. content/uploads/2014/03/some‐gut‐microbes‐ 3. https://nccih.nih.gov/health/probiotics/introduction.htm love‐cheeseburgers.gif Fiber Has a Big Impact Major Groups of Dietary Fiber (chains of sugar)* Fiber Type Examples Non‐starch polysaccharides Cellulose, hemicelluloses (eg, pectin, β‐glucan, arabinoxylans, glucomannans, xyloglucans), plant gums/mucilages & hydrocolloids Non‐digestible oligosaccharides Fructooligosaccharides (FSO) Galactooligosaccharides (GSO) Starch‐based material Resistant starch Soluble corn fiber Novel carbohydrate compounds Polydextrose, mixed‐linked α‐glucans Lignin * Not all are confirmed as meeting the new dietary fiber definition by the FDA. The FDA has not yet finalized the list of what qualifies for the new definition of fiber. To date, only a few fibers have been approved by FDA. Solubility - ability of the fiber to dissolve in water (soluble) or remain as discrete particles (insoluble) Viscosity - the ability of some polysaccharides to thicken when hydrated (gel-forming) Fermentability - degree to which fiber, after resisting digestion, can be broken down by the microbiota

Non-Starch Polysaccharides

Cellulose Hemicelluloses β-glucans Pectins Fructans

Arabinogalactans Glucans Arabinoxylans Inulin Glucuronoxylans Oat β-glucan Oligofructose Xyloglucans Barley β-glucan Galactomannans Pectic substances

Brans Chicory root Brans Cereal grains Fruits Onion Cereals Legumes Oats Vegetables Artichoke Legumes Nuts Barley Legumes Agave Nuts Vegetables Rye Potato Wheat Peas Fruit Sugar beets Bananas Extracted Functional fibers Extracted Garlic

Soluble, Soluble, Soluble, Insoluble, viscous, readily non-viscous, poorly to moderately fermentable readily fermentable fermentable fermentable Slide from Dr. Hannah Holscher 8 Four Clinically Meaningful Fiber Designations Clinically meaningful Clinically demonstrated health Representative fibers designation benefits Insoluble Laxative effect (if particles are Wheat bran, Cellulose Corn sufficiently large, coarse) bran, Fruit fiber, Rice bran fiber Soluble, non‐viscous, readily None at physiologic doses Wheat dextrin, Inulin, fermented Oligosaccharides, α‐ Cyclodextrin, Resistant maltodextrins, Polydextrose, Resistant starch, Soy fiber Soluble, viscous, readily Cholesterol lowering β‐glucan (oats and barley), Guar fermented Improved glycemic control gum (raw, unhydrolyzed), Glucomannan (Konjac), Pectins, Gum arabic Soluble, viscous, non‐ Cholesterol‐lowering Psyllium fermented Improved glycemic control Stool normalization Weight loss McRorie JW and GC Fahey, Clin Nurs Studies 1; 82;2013 Inulin Cellulose β-Glucan

Soluble, non‐ Insoluble Soluble, viscous, readily viscous, readily fermented fermented

Sonnenburg, J. L., & Bäckhed, F. (2016). Diet-microbiota interactions as moderators of human metabolism. Nature, 535(7610), 56-64. 13 Microbiota‐Accessible Carbohydrate (MAC)

• Germ‐free mice (lack microbiota) • Populated with human fecal sample • Give a high or low MAC diet for 7 weeks • Mice on low MAC diet – • 60 % less gut microbial taxa (less diversity) • Reduction primarily in Bacteriodales and Clostridiales • Returned to high MAC diet • Partial recovery of diversity • Offspring lost diversity

Sonnenburg ED et al. Nature 529:212, 2016 Fiber Is Becoming Big Business New FDA Dietary Fiber Definition Dietary fiber is defined as non‐digestible soluble and insoluble carbohydrates (with three or more monomeric units), and lignin that are intrinsic and intact in plants; isolated or synthetic non‐digestible carbohydrates (with 3 or more monomeric units) determined by FDA to have physiological effects that are beneficial to human health. • Prebiotic – • “good” bacteria promoters • natural, non‐digestible food components • linked to promoting the growth of helpful bacteria in your gut • Currently include:

Fructooligosaccharides (FOS) Beta‐glucan soluble fiber Psyllium husk Galactooligosaccharides (GOS) Cellulose Guar Gum Pectin Locust bean gum Hydroxypropylmethylcellulose

• Eat more fruits, vegetables and whole grains Can We Cultivate Our Microbiome Through Diet? PROBIOTIC SPECIES FOOD SOURCES Lactobacillus acidophilus Dairy and non‐dairy yogurt, lassi, kefir, miso, tempeh Probiotic Lessons Lactobacillus helveticus Dairy and non‐dairy yogurt, kefir, Italian and • Turnover quickly Swiss cheese • Don’t have the right Lactobacillus delbrueckii Dairy and non‐dairy yogurt, kefir environment, will not continue subsp.bulgaricus to flourish Lactobacillus plantarum Non‐dairy yogurt, sparkling probiotic drink, • Currently very limited on what probiotic juice, kimchi, fermented beets, pickled we give cucumber, pickled ginger, sauerkraut, green • Don’t understand all the players olives, pickled beans Lactobacillus reuteri Fermented vegetables, dairy products Lactobacillus rhamnosus GG Dairy and non‐dairy yogurt, kefir, kombucha, sparkling probiotic drink Lactobacillus casei Kvass, dairy and non‐dairy yogurt, lassi, probiotic dairy drink, kefir Streptococcus thermophilus Dairy and non‐dairy yogurt, lassi, cow's milk probiotic beverage, kefir Bifidobacterium longum Dairy yogurt, kefir Bifidobacterium bifidum Dairy and non‐dairy yogurt, kefir Bifidobacterium infantis Yogurt, kefir, buttermilk, miso, tempeh, pickles, kimchi, cured meats, some wines and vinegars, sauerkraut, sourdough bread Saccharomyces boulardii Kombucha Vegans, Lacto‐ovo Vegetarians vs Omnivores

• Vegans compared to non‐vegetarians: large counts of Baceroides sp, Bifodobacterium sp, E coli, and Enterobaceriacceae1 • Vegans lower stool pH – assumed greater short chain fatty acid production1 • Provotella group is associated with high‐fiber diet2

1 Zimmer J et al. Eur J Clin Nutr 66:53‐60, 2012 2 Consortium THMP. Nruew 486:207, 2012 Specific Fibers Target Specific Bacteria – metagenomics determines which ones Examples

Cultivating Food Fiber Possible Bacteria Responders •Cereal starches Resistant Starch (starch not digested in the Ruminococcaceae1 small intestine; probably largest source of Rbromii1 energy for colonic bacteria) Roseburia/Eubacterium rectale (butryrate producers) 1 Many plant cell walls Cellulose •Ruminococcus sp1 •Clostridium sp1 •Eubacterium sp1 •Bacteroides sp1

1 Flint, HJ, Scott, KP, Dunccan SH, Petra L, Forano E. Gut Microbes 3:289, 2012 Specific Fibers Target Specific Bacteria Continued

Cultivating Food Fiber Possible Bacteria Responders •Whole grain barley B‐Glucan •Increased Lachnospira1 •Whole grain oats •Reduced Enterobacteriaceae1 •Whole grain rye •Increase beneficial bacteria such as Bifidobacterium and butyrate producers such as Eubacterium and Roseburia2,5‐8 •Increased short chain fatty acid (SCFA) production1,5

1. Vanega SM, et al. Substituting whole grains for refined grains in a 6-wk randomized trial has a modest effect on gut microbiota and immune and inflammatory markers of healthy adults. AJCN 2017. 105:635–50 2. Martinez et al., Gut microbiome composition is linked to whole grain-induced immunological improvements The ISME Journal (2013) 7, 269–280 3Kelly et al., 2007; 4Alminger et al., 2008; 5Bourdon et al., 1999; 6Rose, 2014; 7Wang et al., 2016; 8Angelis et al., 2015; 9Smith et al. 2008 Specific Fibers Target Specific Bacteria Continued

Cultivating Food Fiber Bacteria Cultivate •Chicory root Inulin •5 & 7.5 g/d agave inulin •Onion increased Bifidobacteria and •Artichoke SCFA1 •Agave •Wheat •Bananas •Garlic

1. Holscher HD (2015) Agave Inulin Supplementation Affects the Fecal Microbiota of Healthy Adults Participating in a Randomized, Double-Blind, Placebo-Controlled, Crossover Trial. J Nutr; 145:2025–32 2. Fernandes R (2016). Effects of inulin-type fructans, galacto-oligosaccharides and related synbiotics on inflammatory markers in adult patients with overweight or obesity: A systematic review. Clinical Nutrition. 3. Dehghan P (2014) Oligofructose-enriched inulin improves some inﬂammatory markers and metabolic endotoxemia in women with type 2 diabetes mellitus: a randomized controlled clinical trial. Nutrition;30:418–23. 4. Parnell JA (2009) Weight loss during oligofructose supplementation is associated with decreased ghrelin and increased peptide YY in overweight and obese adults. AJCN; 89:1751–59. 5. Cani PD (2009). Gut microbiota fermentation of prebiotics increases satietogenic and incretin gut peptide production with consequences for appetite sensation & glucose response after a meal. AJCN;90(5),1236-43 6. Dewulf EM (2013). Insight into the prebiotic concept: lessons from an exploratory, double-blind intervention study with inulin-type fructans in obese women. Gut; 62: 1112-21. Specific Fibers Target Specific Bacteria Continued

Cultivating Food Fiber Bacteria Cultivate •Chicory root Inulin •5 & 7.5 g/d agave inulin •Onion increased Bifidobacteria and •Artichoke SCFA1 •Agave •Wheat •Bananas •Garlic

[31] [32, 33] [13, 29– ↓ ↑↓ ↓ ↑ ↑ ↑ ↓ ↑ ↑ ↑ ↑↓ ↑ ↑ ↑ ↑↓ ↑ Microbial diversity

Bifidobacteria

Lactobacilli

Bacteroides

Alistipes

Bilophila

Clostridia

Roseburia

Eubacterium Rectale 40] 35, 38–

References Effects of fats on gut microbiota ausnitzii Bilophila References muciniphila Bacteroides Clostridiales Akkermansia Bifidobacteria Faecalibacte‐ riumpr Lactic acid bacteriaa

High Fat ↓ ↑ ↑ 30, 49, 51, 52] Low Fat ↑ [49] High ↑ ↑ ↑ [26, 49] saturated fat

High ↑ ↑ ↑ [45, 49, 50] unsaturated

(From: Singh et al. J Transl Med (2017) 15:73) Effects of non‐digestible carbohydrates on gut microbiota Bacterial Clostridia Roseburia Eubacteria References abundance Lactobacilli Enterococcus Gene richness Bifidobacteria Ruminococcus

[30, 64–66, Fiber/prebi ↑↑↑ ↑ ↑↑↓ 69–76] otics

[3, 30, 67– Resistant ↑↑↑ ↑ ↑ ↑↑69, 72–74] starch

(From: Singh et al. J Transl Med (2017) 15:73) Effects of special diets on gut microbiota Diet Prevotella Roseburia Eubacteria References Lactobacilli Bacteroides Total bacteria Bifidobacteria Enterobacteria Food constituents Western High animal [26, 29, ↓↓ ↓ ↓ ↑ ↑ fat/protein 48] High Mediter‐ ranean fiber/antioxid [41, 129, ↑↑ ↑↑↑↑↑ ants/UFA low 192] red meat Gluten [125, free No gluten ↓ ↓ ↓ ↓ ↓ ↓ ↑ 126,193 –195] (From: Singh et al. J Transl Med (2017) 15:73) Overview of select gut bacterial genera and species commonly affected by diet. Modified from: Singh et al. J Transl Med (2017) 15:73

Bacteria Associated Physiological Changs References Bifidobacteria SCFA production; improve gut mucosal barrier; lower intestinal LPS levels 166, 167 Clostridiales propionate and acetate producing species Bacteroides Activate CD4 + T cells; propionate and acetate producing species 170‐173 Bilophila Promote pro‐inflammatory TH1 immunity 175,176 Faecalibacterium prausnitzii SCFA production; anti‐inflammatory effects Akkermansia muciniphila Anti‐inflammatory effects 53, 133, 185 Lactobacilli SCFA production; anti‐inflammatory and anti‐cancer activities 168, 169 Roseburia SCFA production 179 Eubacteria SCFA production; form beneficial phenolic acids 180, 181 Ruminococcus Prevotella Enterobacteria propionate and acetate producing species Alistipes Reported in tissue from acute appendicitis and brain abscesses 174 Clostridia propionate and acetate producing species Faecalibacterium prausnitzii SCFA production; anti‐inflammatory effects 183, 184 Proof of Concept (Rodents): Fecal Phyla Changes After Long‐Term Feeding of Each Diet

Replacement Diet Walnut Diet Ratio of Firmicutes to Bacteriodetes Changes

• Firmicutes and Bacteriodetes made up 90% of the microbes present. % of Microbes Detected Microbes % of

Replacement Diet Walnut Diet Example of diet cultivating the microbiome

Fig. 6. Inferred functional capacity of the microbial communities associated with walnut and replacement diet determined by linear discriminative analysis (LDA) effect size (LEfSe) analysis of KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways. Positive LDA scores are enriched in animals eating the walnut diet (green bars) while negative LDA scores are enriched in those animals eating the replacement diet (red bars). https://ars.els‐cdn.com/content/image/1‐s2.0‐S0955286317301110‐gr6.jpg Diet Influences Microbiome

• The diet groups had distinct microbial communities • Walnuts ‐ significantly greater alpha diversity. • Walnuts increased the abundance of Firmicutes • Walnuts reduced the abundance of Bacteriodetes • Walnuts enriched the microbiota for probiotic‐type bacteria including Lactobacillus, Ruminococcaceae, and Roseburia • Walnuts significantly reducing Bacteroides, Anaerotruncus, and Alphaproteobacteria Proof of Concept (Humans)

• Controlled randomized, prospective, cross over design • 194 subjects, male and female • 43 g walnut/day • BMI = 25.1kg/m2 • 2 diet phases 8 weeks each: 1) walnuts and 2) nut–free • Reduced fat or carbohydrate to make up for addition of walnuts • 4 week wash‐out period between diets

Bamberger C, et al. Nutrients. 2018 Feb; 10(2): 244. Results: • Walnuts increased significantly Ruminococcaceae and Bifidobacteria • Walnuts significantly decreased Lachnospiraceae species (Clostridium sp. cluster XIVa species (Blautia; Anaerostipes))

Comparison

• Both human and rodent study found increasing Ruminococcaceae which is a probiotic‐type species Specific Diet Recommendations

• Focus on plant derived food but need all nutrients • American diet too little plant food sources in diet • Avoid going overboard though (greater than recommended fiber intake) • Need wide variety of plant sources so get many different types of fiber – no perfect food • Recommended diets: • MyPlate • DASH Diet • Vegetarian type diets Variety and Moderation https://www.choosemyplate.gov/ Summary

• Gut microbial environment is a dynamic community • Relative abundance of specific microbes can affect one’s health • Diet can influence the growth of specific microbes • Diet can be used to target and cultivate the growth of specific bacteria to influence one’s health • Diet rich in plant foods cultivates a more diverse gut microbiota and better health outcomes • Dietitians should help their patients/clients cultivate their gut microbiome Questions