Source: Science Daily
quote: It's not all that complex. Eat less and exercise more.
quote: Biologist Jeffrey Gordon of Washington University in St. Louis became quite well known a few years ago for a group of very skinny mice in his lab. The mice were skinny because they had no bacteria in their intestines. Gordon had kept them completely bacteria-free. If a bacteria-free mouse eats, food passes right through the intestine, significantly undigested.So without bacteria, the mouse can eat and eat and eat and never gain weight. But when Gordon exposed the mice to "this big, bad, dirty world," as Gibson calls it, the mice suddenly turned their food into more calories and gained weight. So bacteria matter. Apparently, they can digest food far more efficiently.