Selective Research Summary From the World Summit on Gut Microbiota for Health
Vanessa M. Shami, MD, FASGE reviewing Fuhler GM, et al. Gastroenterology 2019 Sep 6.
The 2019 Gut Microbiota for Health World Summit focused on microbiota translational science with clinical significance and included plenary sessions on such topics as the impact of diet, exercise, nutrition, and probiotics on microbiota. Below is a selective representation of data discussed at the summit:
Diet-Microbiota Interaction: A diet low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAPs) is commonly prescribed for irritable bowel syndrome (IBS). A 2017 study demonstrated that this type of diet resulted in adequate symptom relief and a reduction in Bifidobacterium species that could be improved with probiotics. Presenters at the Summit hypothesized that the noted clinical improvement was associated with changes in visceral hypersensitivity. (Staudacher HM, Lomer MCE, Farquharson FM, et al. A diet low in FODMAPs reduces symptoms in patients with irritable bowel syndrome and a probiotic restores Bifidobacterium species: a randomized controlled trial. Gastroenterology. 2017;153(4):936-947.)
Exercise-Microbiota Connection: While exercise is widely recommended by physicians, there is minimal data on its impact on the microbiome. A recent study compared increased physical activity in patients with inflammatory bowel disease versus healthy sedentary controls over 8 weeks. There was no impact on disease activity, with only moderate changes in the microbiome. More research is still required to understand long-term, high-intensity exercise. (Cronin O, Barton W, Moran C, et al. Moderate-intensity aerobic and resistance exercise is safe and favorably influences body composition in patients with quiescent inflammatory bowel disease: a randomized controlled cross-over trial. BMC Gastroenterol. 2019;19(1):29.)
Probiotics and Overall Health: Probiotics are commonly used, but there is limited formal guidance about their benefits (The American Gastroenterological Association is still developing a guideline.). One study of 15 patients compared an 11-strain probiotic versus a cellulose placebo for 4 weeks. This study demonstrated that a one-size-fits-all approach is invalid, as there were considerable differences in colonization by the strain in individuals. More research is still required to better define a personalized probiotic approach. (Zmora N, Zilberman-Schapira G, Suez J, et al. Personalized gut mucosal colonization resistance to empiric probiotics is associated with unique host and microbiome features. Cell. 2018;174(6):1388-1405.e21.)
Clostridium difficle Infection and Zinc: A recent study demonstrated that zinc supplementation in mice alters the gut microbiota and can reduce the minimum amount of antibiotics required for susceptibility to C. difficile infection and exacerbate disease activity by increasing toxin processing. (Zackular JP, Moore JL, Jordan AT, et al. Dietary zinc alters the microbiota and decreases resistance to Clostridium difficile infection. Nat Med. 2016;22(11):1330-1334.)
Note to readers: At the time we reviewed this paper, its publisher noted that it was not in final form and that subsequent changes might be made.
Vanessa M. Shami, MD, FASGE
Fuhler GM, Hecht GA; 2019 Gut Microbiota for Health World Summit Meeting Summary Writing Group. Meeting summary: 2019 Gut Microbiota for World Health Summit. Gastroenterology 2019 Sep 6. (Epub ahead of print) (https://doi.org/10.1053/j.gastro.2019.08.044)