Dec. 20, 2006 — The size of your gut may be partly shaped by which microbes call it home, according to new research linking obesity to types of digestive bacteria.
Both obese mice — and people — had more of one type of bacteria and less of another kind, according to two studies published Thursday in the journal Nature.
A "microbial component" appears to contribute to obesity, said study lead author Jeffrey Gordon, director of Washington University's Center for Genome Sciences.
Obese humans and mice had a lower percentage of a family of bacteria called Bacteroidetes and more of a type of bacteria called Firmicutes, Gordon and his colleagues found.
The researchers aren't sure if more Firmicutes makes you fat or if people who are obese grow more of that type of bacteria.
But growing evidence of this link gives scientists a potentially new and still distant way of fighting obesity: Change the bacteria in the intestines and stomach. It also may lead to a way of fighting malnutrition in the developing world.
Nikhil Dhurandhar, a professor of infection and obesity at Louisiana State University's Pennington Biomedical Research Center, wasn't part of the research, but said it may change the way obesity is treated eventually.
"We are getting more and more evidence to show that obesity isn't what we thought it used to be," Dhurandhar said. "It isn't just (that) you're eating too much and you're lazy."
He said the field of "infectobesity" looks at obesity with multiple causes, including viruses and microbes. In another decade or so, the different causes of obesity could have different treatments. The current regimen of diet and exercise "is like treating all fevers with one aspirin," Dhurandhar said.
