A cold virus may make you obese

The next time you catch a cold, beware - you could be getting fat.

That might be a somewhat flip, and not wholly accurate, characterisation - but scientific studies indicate that obesity can be caught from a fairly common virus that turns human cells into fatty tissue.

The adenovirus-36 is known to cause respiratory and eye infections; scientists now say it can also transform adult stem cells found under the skin into the fat cells of adipose tissue.

The study, widely disseminated in the media and on science-related blogs, was presented earlier this week at the annual meeting of the American Chemical Society, against the background of mounting concern over obesity worldwide.

Magdalena Pasarica, of Louisiana State University in Baton Rouge, who led the study, says it does not suggest that the virus is the sole cause of obesity, nor that everyone infected with adenovirus-36 (Ad-36, as it is referred to among the scientific community) will become fat.

The study, she said, is aimed at identifying "the underlying factors that predispose some obese people to develop this virus, and eventually to find a way to treat it."

This study stems from earlier editions that involved research on animals; these studies suggest that Ad-36 and related viruses Ad-37 and Ad-5, can trigger obesity.

Further research established a high prevalence of adenovirus in overweight people.

Leading on from this, scientists now suggest that respiratory viruses play an important role in triggering the tendency towards obesity in people who, thanks to their sedentary lifestyle, are predisposed to putting on weight.