Scientists at Firmenich, a company in Geneva that researches flavours and smells for the food and perfume industry, took samples of armpit sweat from 24 men and 25 women after they had spent time in a sauna or 15 minutes on an exercise bike.

When the samples were analysed, the team found those from women contained high amounts of an odourless sulphur-containing compound, according to New Scientist magazine.

When this mixed with bacteria usually found under the arm, it was transformed into a chemical called thiol, well known for its onion-like smell.

Men however sweat in a different way - scientists found high levels of an odourless fatty acid which released a cheesy smell when exposed to enzymes produced by bacteria in the armpits.

Christian Starkenmann, who led the study, said: Men smell of cheese, and women of grapefruit or onion.

A team of independent testers recruited by the scientists also found the smell from womens armpits was more unpleasant.

It is thought the study could be used to develop deodorants aimed specifically at men or women.

Not all scientists are convinced the experiment can be repeated outside Switzerland however as people have different diets and genes elsewhere in the world.

Professor Tim Jacob, who researches the science of smell at Cardiff University, said: Other factors include what you eat, what you wash with, what you wear and what genes you inherit.

Last month it was reported that a woman can subconsciously tell when a man is sexually attracted to her by the smell of his sweat.

According to researchers from Rice University in Texas, men sweat different according to what mood they are in and womens brains can pick up if a man is interested in her.