From the desk of: Steve Zeisel, M.D., Ph.D.
Gut microbes have been making a lot of news lately. As the name implies, these bacteria reside in the intestine and fulfill a variety of functions essential to our health, specifically ensuring that we digest foods properly. But that’s only the beginning. A recent study shows that gut microbes can also determine your weight.
THE STUDY
Gut microbes were harvested from 4 pairs of women who were twins. One twin was thin and the other twin in each pair was obese. The microbes were transplanted in mice. The mice getting the microbes from the obese twin became fatter while the mice getting microbes from the paired lean twin did not get fatter.
WHY IS THIS IMPORTANT?
Until recently we did not realize that the microbes that we house in our guts have an important role in nutrition and metabolism. This study demonstrates that obese people have different microbes in their guts than do lean people and these microbes can change our body weights. How do they do this? We do not yet know but perhaps these microbes make calories more available from hard to digest foods, or perhaps they make signals that disturb how we respond to hormones like insulin.
WHAT THIS MEANS FOR YOU
Our gut microbes are influenced by what we eat. Vegetarians have different microbes than do meat eaters. Some foods, like yogurt, contain bacteria and may help change our microbes. Antibiotics used to treat infections, also can make big changes in our bacteria. Babies delivered vaginally are populated with very different bacteria than babies delivered by C-section.
Reference: Gut microbiota from twins discordant for obesity modulate metabolism in mice. Science. 2013 Sept 6;341(6150):1241214. doi: 10.1126/science.1241214. PMID: 24009397.
