Women handle stress better after smelling their boyfriend's shirt. iStock

Smelling a boyfriend's shirt can help women react better when confronted with stressful situations, a study has found.

While the comfort of our loved ones helps us on a psychological level, a new study shows that it also has beneficial effects on our bodies.

Researchers from the University of British Columbia, Canada, have found that women who smelled their partner's t-shirt before and after a stressful scenario anticipated the demanding situation better and recovered quicker than others. Researchers published their findings in the Journal of Personality and Social Psychology.

The study was conducted on 192 people – 96 heterosexual couples. In order to conduct the experiment, the men were asked to wear a t-shirt for 24 hours. They were specifically asked to shower using only unscented soaps and to not wear any deodorant, so that it would only be their smell on the t-shirt and no other scent. They were also asked to use unscented detergent for their bedsheets. They were also kept in the dark about what the t-shirt would be used for.

On the day of the experiment, women were presented with three t-shirts samples, but not told which one was which. One t-shirt had been worn by their partner, one had been worn by a complete stranger and the third one hadn't been worn at all.

They were then confronted with stressful scenarios – a mock job interview they only had 5 minutes to prepare for and on-the-spot mental calculus questions. Their stress levels were monitored at all times during the procedures.

It came out that women who smelled their partner's shirt less than 15 minutes before the job interview and maths test anticipated the tasks better than the women who smelled unworn t-shirts or t-shirt worn by strangers. If they smelled their partner's shirt up to 23 minutes after the job interview and mental calculus, they recovered faster than the others as well and showd lower stress levels.

"Many people wear their partner's shirt or sleep on their partner's side of the bed when their partner is away, but may not realiSe why they engage in these behaviours," said Marline Hofer, who led the study. "Our findings suggest that a partner's scent alone, even without their physical presence, can be a powerful tool to help reduce stress."

On the other hand, women who smelled a stranger's t-shirt had higher level of cortisol – the stress hormone – in what the study identifies as a "stranger danger" effect. Hofer thinks it's because humans are raised to see strangers as potential threats: "From a young age, humans fear strangers, especially strange males, so it is possible that a strange male scent triggers the 'fight or flight' response that leads to elevated cortisol," she said.

The study suggests that the scent of a loved one is a natural stress buffer that can be applied to everyday life. The study's senior author, Frances Chen, says that something "as simple as taking an article of clothing that was worn by your loved one" could help with stress when someone's travelling abroad or moving.