The diversity of germs in the human gut suggests microbiota play a greater role in health than previously thought, even driving obesity and other metabolic conditions
The genetic profiles of microbes from the human gut are helping scientists better understand what flora communities are normal and what might be the signs (or causes) of illness. Many microbes, such as these C. difficile can be harmful in big numbers, but a balance of bacteria in the gut can actually keep people healthy--and maybe even slim.
Outnumbering our human cells by about 10 to one, the many minuscule microbes that live in and on our bodies are a big part of crucial everyday functions. The lion's share live in the intestinal tract, where they help fend off bad bacteria and aid in digesting our dinners. But as scientists use genetics to uncover what microbes are actually present and what they're doing in there, they are discovering that the bugs play an even larger role in human health than previously suspected—and perhaps at times exerting more influence than human genes themselves.
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