This article is from the WSSF 2015 AFRMA Rat & Mouse Tales news-magazine.

Did You Know?  If you don’t have a healthy gut microbiota, this can lead to immune dysregulation that is passed on to future generations. Studies done on mice with microbes from a human donor show the connection between diet and microbiota composition and function. Diets low in fiber leads to depletions of necessary gut bacteria of which there are thousands of distinct bacterial species. Fiber is the primary food source for gut bacteria which fends off pathogens, trains the immune system, and guides the development of tissues.

Researchers at the Stanford University School of Medicine found that mice fed a low-fiber diet had a 75 percent reduction in microbial diversity after only a couple weeks. By the fourth generation on a low-fiber diet, some mice had up to three-quarters reduction of intestinal bacteria compared to their great-grandparents. In one study, the researchers were able to fully restore the mouse’s bacterial profiles by introducing fecal contents of fourth-generation high-fiber-diet mice into the intestines of fourth-generation low-fiber mice, along with putting them on the high-fiber diet for two weeks.

Mice on a fiber-free diet had a dramatically diminished mucus layer which can cause ulcerative colitis. Whereas mice fed high-fiber chow and fiber-free chow on alternating days was not enough to keep the gut healthy and these mice had a mucus layer about half the thickness of mice on the consistently high-fiber diet. Just eating right may no longer be enough to restore these lost species in the gut.

Mice on the high-fiber diet consumed fewer calories and were slimmer than those on the fiber-free diet.

Article on Stanford News Center Low-fiber diet may cause irreversible depletion of gut bacteria over generations and one in Scientific American Fiber-Famished Gut Microbes Linked to Poor Health. Study Starving our Microbial Self: The Deleterious Consequences of a Diet Deficient in Microbiota-Accessible Carbohydrates Cell Metabolism, Volume 20, Issue 5, 4 November 2014, Pages 779–786.