Visit 1: Microbiome Stool pH

Transcript

1. The Microbiome and Importance of Intestinal pH MICROBIOME GROUP SHARED MEDICAL APPOINTMENTS
2. 40 trillion microorganisms from >1000 species (50% bacterial) 23,000 vs. > 1 million genes 60% of our immune system is located in our gut Provide crucial functions Regulate metabolism Protect against infections Promote normal GI function, digestion Synthesize certain essential nutrients Bidirectional communication/education The Microbiome 2
3. Earle KA et al. Cell Host Microbe. 2015;18(4):478–488 3 So photogenic…
4. Agriculture thousands of years ago 200 100 50 150 Processed, Western Diet 10 Hunting/Gathering 100-150 g 35 g 15 g Evolution of Fiber Intake Over the Years Slide credit: Justin Sonnenberg 4
5. Beneficial/commensal Harmful/opportunistic Balanced gut microbiota Gut permeability Proinflammation Insulin resistance Gut/metabolic/cardiovascular health Harmful/opportunistic Beneficial/commensal Gut microbial dysbiosis Gut permeability Gut/systemic inflammation → GI sxs Insulin resistance Adiposity, diabetes, MetS, CVD, NAFLD, NASH, IBD, IBS, etc. Prudent diet & lifestyle, probiotics/prebiotics High-fat/high-sugar diets, sedentary, antibiotic use Dysbiosis
6. Intestinal pH is crucial for Gut Microbiome  pH stands for “power of hydrogen” & is measured on a scale from 0 to 14 – neutral is 7.0 – anything below 7 is considered acidic, and anything above 7 is considered alkaline.  A healthy, optimal pH for the colon is between 5.0 to 6.5, which is considered acidic since it is below the neutral pH of 7.0. At this acidic pH, the growth of pathogens is inhibited. A pH of below 5.0 is potentially concerning. Stool pH is relevant to a variety of GI symptoms and issues.  Potentially problematic species such as E. coli, Bacteroides, and Desulfovibrio and yeast species such as Candida begin to proliferate when the pH starts to rise above 7.0.
7. How fast can stool pH change?  Studies show that increasing levels of fiber in the diet can rapidly decrease the pH within just a couple of weeks  In one study, people who doubled their fiber intake from 17 g to 34 g per day experienced a progressive drop in stool pH over a mere 2 weeks.  Goldilocks level for pH – not too high or too low (usually problem is too high) although in those with diarrhea it can become too low due to loss of beneficial acids S.B. Naaeder, D.F. Evans, and E.Q. Archampong, “Effect of Chronic Dietary Fibre Supplementation on Colonic pH on Healthy Volunteers,” West African Journal of Medicine 17, no. 3 (July-September 1998): 165-167
8. Strongly affects cancer risk  Studies also show that higher stool pH above 7.5 is associated with increased risk of colon cancer, likely due to the production of carcinogenic compounds  A process called protein putrefaction, where bacteria break down protein to form harmful compounds, occurs much more at alkaline pH.  At higher pH pathobiont bacteria (bacteria that can be either harmless or harmful at certain times) such as Bacteroides, E. coli (yes) and Clostridia ferment proteins to produce amines, indoles, and ammonia, which have negative effects on gut permeability, inflammation and motility.
9. Impacts colonic cancer risk  Additionally, our primary bile acids, produced by the liver to aid in digestion, can be fermented by pathobionts into so-called secondary bile acids, which are potential carcinogens because they can cause DNA damage in our colonic cells and inflammation – a process that only occurs at neutral or alkaline pH.  The growth of pathobionts such as Bacteroides, and their ability to produce all these potentially harmful compounds, depends heavily on colon pH. CK Yao et al., "Review article: insights into colonic protein fermentation, its modulation and potential health implications," Aliment Pharmacol Ther, 43 no. 2 (2016):181-96
10. Improves mineral absorption  An acidic pH is critical for absorbing certain minerals such as calcium (FOOD>SUPPS) and iron. Their absorption declines when the pH starts getting into the alkaline range.  So, maintaining this acidic pH is crucial to maintaining healthy absorption and optimal digestive function, preventing dysbiosis, and preventing colon cancer.
11. Infant Microbiome deteriorating  Unfortunately, stool pH in the infant gut microbiome worldwide has been steadily increasing from 1926 through current times, from an average of 5.0 up to 6.5, likely as a result of decline in beneficial keystone SCFA producing species such as bifidobacteria.  There has been a corresponding rise in dysbiosis seen in the infant microbiome during this time  Dysbiosis in infant microbiota has been linked to long-term health implications such as higher risk of developing autoimmune disorders, chronic inflammation, asthma, and other immune-mediated diseases.
12. How to maintain optimal stool pH  One of the biggest contributors to healthy pH are short chain fatty acids, which are produced by our healthy bacteria. The most important and well-known of these SCFAs is butyrate, which has several beneficial properties.  As we discussed in our previous group, butyrate is the primary fuel for the intestinal cells, reduces G.I. and systemic inflammation, promotes normal intestinal permeability, has anti- cancer effects, improves the gut-brain axis and can even heal “leaky brain”, an impaired blood-brain barrier.
13. Prebiotic plant fibers  The best way to increase production of short chain fatty acids is a high- fiber diet with a diverse blend of plenty of plant fiber, which will be used by the good bacteria to produce SCFAs.  Your bacteria use the fibers in these prebiotic foods to produce short- chain fatty acids.
14. Additional fiber  For additional fiber the options are either taking either psyllium husk or Partially Hydrolyzed Guar Gum (to help with constipation or diarrhea or to potentially help lower pH if your numbers are too high)  Do keep in mind that the lab usually has a normal range of 7.0-7.5 for stool pH, but optimal is 5.5-6.5  Both fibers have the effect of increasing the production of short-chain fatty acids, and thereby acidifying the intestine and lowering its pH.
15. Psyllium  Psyllium has been shown to help raise the levels of three groups of beneficial bacteria known to produce butyrate — Lachnospira, Roseburia, and Faecalibacterium — especially in patients with constipation.  Of note, psyllium has major systemic benefits, including reducing cholesterol, reducing blood pressure, increasing satiety and thus supporting weight loss, and potentially alleviating IBS symptoms.
16. PHGG or Partially Hydrolyzed Guar Gum  Thriving in a hot, arid climate, the guar bean is native to India but has been cultivated worldwide now for over a century. Made by grinding and drying the guar bean, PHGG has unique and potent properties as a prebiotic.  In addition to helping elimination, Partially Hydrolyzed Guar Gum can help balance your microbiome, reduce small intestinal bacterial overgrowth (SIBO), alleviate IBS symptoms, and selectively feed some beneficial bacteria. It can be helpful in constipation or diarrhea.
17. PHGG  It increases levels of keystone species such as Fecalibacterium, Bifidobacteria, and Bacteroides and boosts the production of short-chain fatty acids such as butyrate and acetate.  PHGG has shown additional systemic benefits such as regulating blood sugars by slowing the uptake of glucose from the intestine, promoting satiety, and lowering cholesterol levels.  My preferred form of PHGG is a patented product called SunFiber®, and there are various brands that contain this product, such as Tomorrow’s Nutrition and Perfect Pass.
18. Levels are increased by polyphenols, inulin, and arabinoxylans: • Polyphenols – green tea, beans, red wine and kiwi • Inulin – Jerusalem artichoke, jicama, chicory, onion, garlic, asparagus and leek • Arabinoxylans – rye, barley, rice, oat and sorghum Review: 20 Prebiotic Foods That Support Faecalibacterium Prausnitzii
19. Fermented foods  Fermented foods contain organic acids such as lactic acid and acetic acid that contribute to maintaining the healthy acidity in the colon.  Vinegar is defined by its content of acetic acid; consuming fermented foods that contain vinegar (or ACV) delivers the acetic acid to the intestine, where it helps keep pH at a healthy low level.
20. Follow-up  Stool pH will be ordered at the Sutter lab or Quest Diagnostics if you typically use that lab (message me if you do not want to do this test for any reason)  Pick up collection container from the Sutter lab (order will be placed electronically today)  Return the collection container after stool sample collection  Any questions?