If people are scrunching their noses around you every time you go to the gym, you may not have a body odor problem. It may just have a polyester problem. That is, according to new research that claims that polyester is a more ideal breeding ground for smelly bacteria than cotton.

It may come as a surprise, but sweat itself does not have a pungent odor. Chris Callewaert, a researcher at Ghent University, Belgium, explains that the long-chain fatty acids our body secrets in sweat are just too big to be volatile, and thus cannot produce odor. However, bacteria on skin and in our clothes can catch these acids and break them down into smelly molecules.

Corynebacteria are the main causes of bad odors in the armpits, but these anaerobes fail to grow on textiles. According to Callewaert, the main odor-factory in clothes is a bacterium called micrococci.

"They are known for their enzymatic potential to transform long-chain fatty acids, hormones, and amino acids into smaller-volatile-compounds, which have a typical malodor," he explained in a recent statement.

Callewaert suspects that this bacterium grows exceptionally well on polyester, which is why people wearing the material tend to smell worse than cotton wearers when exercising.

In a study recently authored by Callewaert and slated to be published in the journal Applied and Environmental Microbiology, investigators collected t-shirts from 26 healthy individuals following an intensive, hour-long exercise session. These shirts were incubated for 28 hours and then inspected by a trained odor panel. They were also analyzed for the presence of specific types of bacteria.

It was found that polyester clothing indeed appeared to boast the most pungent and powerful of odors, while pure cotton clothes were the least insulting to the nose.

He says that research like this is especially important for people suffering from body odor.

"BO is taboo, and its prevalence is greatly underestimated," he said. "There is little these people can do to help themselves. Some of them are too psychologically distressed to talk to strangers, or even to leave the house, afraid of what people might think of their smell."

By understanding some of the factors that might contribute to an intense odor, steps can more effectively be taken to counteract the pungent problem.