A cold-like virus may cause obesity, new experiments suggest. Researchers at the University of Wisconsin in Madison have found that mice and chickens infected with a common human virus put on much more fat than uninfected animals. They have also discovered that the same virus is more prevalent among overweight people, a strong indication that it may also cause obesity in humans. In four experiments, the Wisconsin researchers inoculated chickens and mice with adenovirus-36, a member of a viral family that includes about 50 strains.
Most adenoviruses cause colds, diarrhea or pinkeye.
After several months, animals infected with adenovirus-36 weighed only 7 percent more on average than those without the virus, but their bodies contained more than twice as much fat. It is also the first virus the researchers looked at, raising the possibility that other human viruses may also cause obesity. Dhurandhar and his colleagues picked adenovirus-36 simply because little is known about it and the strain is relatively easy to work with. Their study is being published in the August issue of the International Journal of Obesity. But they strongly suggest that infection plays an important role.