You and Your Microbiome

Two recent findings on different subjects highlight the importance of the community of bacteria in our gut, called our microbiome.

First up is an article detailing the effects of exercise on our microbiomes. Researchers at the University of Illinois Urbana-Champaign showed that a few weeks of moderate exercise by people who were not exercising previously alters the number and types of bacteria found in their guts. And although the types of bacteria were not the same in everyone, in general there were increases in the types of bacteria that reduce inflammation, fight insulin resistance, and enhance metabolism. The changes were not permanent, however; the bacterial community reverted back to the original state when the subjects quit exercising. The authors speculate that some of the benefits of exercise may be due to the effects of exercise on our biomes. A New York Times article discusses this topic in some depth.

On an entirely different subject, scientists may have discovered at least part of the explanation for why dietary fiber is good for you. It turns out that although we humans can't digest dietary fiber, some of the bacteria in our gut can. It's their major food supply! More dietary fiber means more bacteria, some of which reward us by supplying us with certain nutrients that we can use. In addition, bacteria signal the cells lining the gut to produce more mucus. A thick mucus coat on the inner surface of the gut is important; it protects the gut cells from damage and prevents the immune system from overreacting to the presence of so many bacteria. A more detailed explanation of this subject can be found here, for those who are interested.