dietary interventions to prevent a leaky gut · dietary sources of fiber • fiber can be found in:...
TRANSCRIPT
Dietary Interventions to Prevent a Leaky Gut
Dr. Jennifer Monk
Assistant Professor Department of Human Health & Nutritional Sciences
University of Guelph
What is Gut Health?
• Positive aspects of gastrointestinal (GI) tract function, such as:
– effective digestion and absorption of food
– absence of GI illness
– immune function
– Focus on the colon (gut)
• Gut Health Interface
– Gut Microbiota (bacteria)
– GI barrier (human cells next to the microbiota)
• Impair gut health development of diseases
Nagpal et al., 2014, Front Med GI Barrier
&
What is the Gut Microbiota?
• Gut = colon or large intestine
• Microbiota = collection of all bacteria (or microbes) living in/on the human body
• 200-500 different species of bacteria per person
• Microbiota composition and size changes throughout the GI tract (mouth colon)
• The biomass of the microbiota is in the colon
Symbiotic Relationship Between the Human Body and the Microbiota
The human body exists in a delicate balance with our bacteria
Maintaining balance is central to preventing disease
Da Silva et al., 2017
Our health depends on the health of our microbes
• Bacteria/microbial cells outnumber
human cells by approximately 3:1
• Bacteria influence how the body functions…it can promote health or promote disease development
https://www.amnh.org/explore/science-topics/microbiome-health/meet-your-microbiome
FEMS Microbiol Rev. 20160 Jan; 40(1): 117–132.
Microbiota Impacts Many Physiological Functions
Obesity and
Insulin Resistance
Inflammation
Environmental Factors Impacting the Gut Microbiota
Sommer et al., Nature Reviews Micro, 2013
Balance Promote Heath &
Physiological
Function
Promote Disease
Dysbiosis
(out of balance) Microbiota Composition
Altered Gut
Microbiota
Dietary Components Influence the Gut Microbiota
Gut Microbiota
DYSBIOSIS PROMOTE
HEALTH
Obesity/Insulin
Resistance
High Fat Diet Fruits and Vegetables
Pulses Whole Grains Artificial Sweeteners
-
-
+
+
+
Yogurt
Dairy Products
+
The GI Barrier: the other side of Gut Health
Single cell barrier separating the external environment and microbiota from the rest of the body.
Defense of this single cell barrier is critical!
• PIC
Van den Bossche et al., 2017
microbiota
The GI Barrier & the Microbiota: a Critical Gut Health Interface
Epithelial Cell/Colonocyte
Microbiota
GI Barrier Components
Anti-microbial
proteins (AMPs)
Microbiota
Mucus Layer (made up of mucins)
Hold barrier cells tightly together
Single cell thick GI Barrier
Physical Separation of Microbiota from the GI Barrier
Maynard et al., Nature, 2012
www.biokplus.com
What Happens When the GI Barrier Fails?
How Can We Improve our Gut Health?
1. Change the composition and function of the microbiota
2. Improve the function of the GI Barrier Less leaky More mucus
Anti-microbial
proteins
(AMPs)
Microbiota
Mucus Layer (made up of mucins)
Holds barrier cells tightly together
Single cell thick GI Barrier
3. Both
Maynard et al., Nature, 2012
Can Our Nutritional Choices Influence Gut Health?
Danneskiold-Samsoe et al., Food Res Int, 2019
Food Components
Carbohydrates Proteins
Lipids Phenolic
Compounds
Producing
SCFA BCFA
TRP-metabolites Secondary Phenolics
Gut Health Interface
Health Effects
Dietary Components that Reduce Leaky Gut
• Phenolic Compounds
– Catechins apples, dark chocolate, blackberries, cherries
– Quercetin leafy vegetables, broccoli, red onions, peppers, apples, grapes
– Epicatechin green tea, apples, cocoa products, red wine
– Caffeic acid coffee, berries, apples, artichokes
– Resveratrol red wine, red grapes
– Isoflavones soybeans, chickpeas, fava beans, pistachios, peanuts,
Monk et al., JNB, 2015-2020; Piegholdt et al., FRBM, 2014; Noda et al., 2012; Kullamethee et al., PNS, 2013; Mayangsari et al., JFF, 2018; Suzuki et al., J Nut, 2009
• Omega-3 fatty acids - EPA/DHA fatty fish, available in supplements
• Fiber
- Soluble fiber - Oligosaccharides
Dietary Sources of Fiber
• Fiber can be found in:
– Fruits and Vegetables
– Legumes/pulses: dried beans, lentils, peas, soybeans
– Nuts and seeds
– Whole grains (“brown”): breads, cereals, crackers and pasta, brown rice, hulled barley, oats
Smolin et al., Nut, Sci App, 2015
Liver Artery
Intestine Effect of Dietary Fiber
• ↓ Total Cholesterol
• ↓ LDL-cholesterol
• ↓ CVD risk
aaaaaaaaaaaaaaaaaaa
For every 7 g dietary fiber/day DECREASES CVD risk by 9%
Fiber Cholesterol
Beneficial Health Effects of Fiber
Smolin et al., Nut, Sci App, 2015
• Slows passage of food through GI tract
• Slows the absorption of nutrients in the GI tract
• Increases satiety = feeling “full” longer
• Slows glucose absorption
• ↓ fluctuations in blood glucose
• Improves bowel regularity
(↓ constipation)
• ↓hemorrhoids
• ↓ diverticulosis/diverticulitis
• ↓ risk of colon cancer
High Fiber Intake Low Fiber Intake
Time after eating
Blo
od
Glu
cose
Low soluble fiber meal
Soluble fiber-rich meal
How Dietary Fiber Can Improve Gut Health
https://www.thinkbiome.com/postbiotics Epithelial Cell/Colonocyte
Tight Junctions
https://www.thinkbiome.com/postbiotics
http://www.pulsecanada.com/about-pulse-canada/what-is-a-pulse/
Dried edible seeds that grow inside a pod
Pulses are lower in fat versus soybeans and peanuts
Dietary Pulses
• Affordable
• Nutrient Dense – Low fat
– High protein
– High fiber
– High in vitamins and minerals
• Example: one cup of beans (~2/3 can) = ~12 g fiber…HALF the daily recommended fiber intake
http://www.pulsecanada.com/about-pulse-canada/what-is-a-pulse/
Chronic Conditions in Canadian Adults: Leaky Gut Plays a Role
https://www.canada.ca/en/public-health/services/chronic-diseases/prevalence-canadian-adults-infographic-2019.html
Metabolic Syndrome
Obesity
High Triglycerides
Low HDL cholesterol
“good cholesterol” Hypertension
High blood glucose
Metabolic Syndrome
“Dyslipidemia”
CLUSTER of inter-related conditions that INCREASE RISK of developing: • Atherosclerosis • Heart Attack • Stroke • Type 2 Diabetes
“Hyperglycemia”
CVD
Chronic INFLAMMATIONN
If you answered “Yes” to 2 questions, you may be at risk of developing metabolic syndrome. If you answered “Yes” to 3 or more questions, you may have metabolic syndrome.
Metabolic Syndrome Prevalence
18-39 40-49 50-59 60-69 70-79
Age (years)
40% 40%
20%
% o
f th
e P
op
ula
tio
n
0%
https://www.metabolicsyndromecanada.ca/
https://infophentermine.com/body-mass-index/
How do We Assess Overweight/Obesity
Classified based on Body Mass Index (BMI)
BMI
Higher the BMI, higher the CVD risk
Severely Obese
Morbidly Obese
Adipose
Tissue
Ser
um
LP
S
Lean Obese Inflammatory Mediators
Insulin
Sensitivity
Adipose Tissue (local) and
Systemic Inflammation
Gut Microbiota
Cancer
Hypertension
Cardiovascular Disease
Type 2 Diabetes
LPS How does the microbiota contribute
to the development of obesity?
Obese Inflammatory Phenotype
Amar et al. J Clin Nutr, 2008
Insulin
Resistance
Goblet
Cell
Tight
Junctions
Mucins Mucus
Layer
HEALTHY OBESE
Blood
The Gut Health Interface Changes in Obesity
1. Changes in Gut
Microbiota
2. LOSS of mucus
and tight junctions
3. Increased GI
Barrier
Permeability
(Leaky Gut)
Gut
Microbiota
Epithelial
Cell
4. LPS and other bacteria
components enter the blood
stimulating inflammation and
metabolic dysfunction
Take Home Messages
• Gut Health comprises the function of BOTH the microbiota and GI barrier
• Improving GI barrier function can reduce the severity of many chronic diseases
• Our nutrition or dietary choices can profoundly impact gut health
• Eat more fiber!