Gut infections keep mice lean
Bacteria can invade one rodent from another, preventing both from getting fat
MICROBE DIET Mice fed microbes from obese people tend to gain fat. Microbes from lean people protect mice from excessive weight gain, even when animals eat a high-fat, low-fiber diet.
Kay Chernush/Getty Images; Kuttelvaserova Stuchelova/Shutterstock
Skinniness could be contagious. Gut bacteria from thin people can invade the intestines of mice carrying microbes from obese people. And these invaders can keep mice from getting tubby, researchers report in the Sept. 6 Science.
“It’s very surprising,” says molecular microbiologist Andreas Schwiertz of the University of Giessen in Germany, who was not involved in the work. “It’s like a beneficial infection.”
But the benefits come with a catch. The invading microbes drop in and get to work only when mice eat healthy food. Even fat-blocking bacteria can’t fight a bad diet, suggests study leader Jeffrey Gordon, a microbiologist at Washington University in St. Louis.
In recent years, researchers have collected clues that suggest that gut microbes can tweak people’s metabolism.
Fat and thin people have different microbes teeming in their
