A new study has revealed that a man's sweat is responsible for increased levels of cortisol hormone in women, which leads to higher sexual arousal and faster heart rates.

The study says that male sweat releases a pheromone, which when sniffed by woman boosts the level of cortisol. The study was conducted by researchers at the University of California at Berkeley.

The main focus of the study was on androstadienone, a chemical that is a derivative of testosterone. Previous studies have already revealed that androstadienone was found to affect women's mood, sexual and physiological arousal and brain activation. Androstadienone is found in male sweat, saliva and semen and has a musky smell.

Researchers analyzed the levels of cortisol in around 48 women, with an average age of 21, after they took 20 sniffs from a jar of androstadienone. Cortisol is a hormone secreted to maintain arousal stress levels. Researchers found that the cortisol levels in the women shot up leading to improved mood, higher sexual arousal, blood pressure, heart rate and breathing.

The women were also made to sniff baking yeast in order to compare with the results, but researchers did not find the same response. Says Claire Wyart, a postdoctoral researcher in the Berkeley Olfactory Research Program, leader of the study, "Many people argue that human pheromones don't exist, because humans don't exhibit stereotyped behavior. Nonetheless, this male chemical signal, androstadienone, does cause hormonal as well as physiological and psychological changes in women."

The study has been published in the latest issue of The Journal of Neuroscience.