http://www.msnbc.msn.com/id/16296772/
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.
In one study, Gordon and colleagues looked at what happened in mice with changes in bacteria level. When lean mice with no germs in their guts had larger ratios of Firmicutes transplanted, they got “twice as fat” and took in more calories from the same amount of food than mice with the more normal bacteria ratio, said Washington University microbiology instructor Ruth Ley, a study co-author.
It was as if one group got far more calories from the same bowl of Cheerios than the other, Gordon said.
In a study of a dozen dieting people, the results also were dramatic.
Before dieting, about 3 percent of the gut bacteria in the obese participants was Bacteroidetes. But after dieting, the now normal-sized people had much higher levels of Bacteroidetes — close to 15 percent, Gordon said.
“I think that gut bacteria affects body weight,” said Virginia Commonwealth University pathology professor Richard Atkinson, who wasn’t part of the research team and is president of Obetech Obesity Research Center in Richmond. “I don’t think there’s any doubt about that and they showed that.”