Partner’s Scent Can Improve Sleep
The scent of a romantic partner can help improve sleep, according to a new Canadian study from the University of British Columbia (UBC).
The findings, published in the journal Psychological Science, show that participants who were exposed to their partner’s scent overnight had better sleep quality, even though their partner was not physically present.
“We saw an effect similar in size to what has been reported from taking oral melatonin supplements — often used as a sleep aid,” said Marlise Hofer, the study’s lead author and a graduate student in the UBC department of psychology.
Research has linked the physical presence of a long-term romantic partner to positive health outcomes such as a sense of safety, calm and relaxation, which in turn can lead to better sleep, say the investigators.
By signaling recent physical proximity, the mere scent of a partner may have similar benefits.
“Our findings provide new evidence that merely sleeping with a partner’s scent improves sleep efficiency. Our participants had an average sleep efficiency improvement of more than two per cent,” said Hofer.
For the study, the team analyzed sleep data from 155 participants who were given two identical-looking t-shirts to use as pillowcases — one had been previously worn by their romantic partner, and the other had either been previously worn by a stranger or was clean.
To capture body odor on the t-shirts, the participants’ partners were given a clean t-shirt to wear for 24 hours, and were asked to refrain from using deodorant and scented body products, smoking, exercising and eating certain foods that could affect their body odor. The t-shirts were then frozen to keep the scent.
Next, each participant received two t-shirts to place over their pillows, without knowing which one was which. They spent two consecutive nights sleeping with each t-shirt. Each morning, they filled out a survey about how well-rested they felt.
Their sleep quality was also objectively monitored with an actigraphy sleep watch that tracked their movements throughout the night. At the end of the study, participants guessed if the shirts they had been sleeping with had previously been worn by their partner.
The results show that participants felt more well-rested on the nights they thought they were sleeping with their partner’s scent. Importantly, regardless of the participants’ beliefs about scent exposure, the sleep watch data also indicated that their sleep improved when they were actually exposed to their partner’s scent.
“One of the most surprising findings is how a romantic partner’s scent can improve sleep quality even outside of our conscious awareness,” said Frances Chen, the study’s senior author and associate professor in the UBC department of psychology.
“The sleep watch data showed that participants experienced less tossing and turning when exposed to their partners’ scent, even if they weren’t aware of whose scent they were smelling.”
Hofer says the results could pave the way for future research examining the efficacy of simple and effective methods of improving sleep, such as bringing a partner’s shirt the next time you travel alone.
The team is currently recruiting participants for a pilot study to investigate whether the scent of parents can improve their infant’s sleep quality.
Source: University of British Columbia
Pedersen, T. (2020). Partner’s Scent Can Improve Sleep. Psych Central. Retrieved on February 28, 2020, from https://psychcentral.com/news/2020/02/14/partners-scent-can-improve-sleep/154188.html