For some people, sleeping next to the one they love provides comfort and security, along with endless opportunities for snuggling. For others, dealing with someone’s tossing and turning—not to mention snoring—leads to sleepless nights and one or both people waking up on the wrong side of the bed. But a new study shows that sleeping with your beloved’s clothing can actually be as effective as a nighttime dose of melatonin, so you might want to think twice before using their ratty t-shirt as a dust rag.
According to a new study from the University of British Columbia, participants who were exposed to their partner’s scent overnight experienced better sleep quality, even if their partner wasn’t actually sleeping next to them. Researchers looked at sleep data from 155 participants, each of whom were given two identical-looking t-shirts to use as a pillowcase. One of the tees had been previously worn by their romantic partner, and the other had either never been worn or had been worn by a stranger, and they were not told which was which ahead of time.
In order to adequately, ahem, capture their unique scent, the participants’ partners wore the t-shirt for 24 hours, and they were asked to refrain from using deodorant and scented body products, smoking, exercising, and eating certain foods that might affect their body odor. The shirts were then frozen to preserve their unique scent before the study.
The participants then spent two consecutive nights sleeping with each tee, filling out a survey the following morning noting how well-rested they felt. Their sleep activity was also monitored using an actigraph sleep watch, which tracked their movements throughout both nights.
Per the findings, “At the end of the study, participants guessed if the shirts they had been sleeping with had previously been worn by their partner.” And it turns out, the night they spent cuddled up next to their loved one’s tee resulted in a more restful slumber. “Participants reported feeling more well-rested on the nights when they believed they were sleeping with their partner’s scent. Moreover, regardless of their beliefs about scent exposure, data from the sleep watches indicated that objective sleep improved when participants were actually exposed to their partner’s scent.”
Marlise Hofer, the study’s lead author and a graduate student in the UBC department of psychology, confirmed the findings, noting, “Our findings provide new evidence that merely sleeping with a partner’s scent improves sleep efficiency,” with data showing an “average sleep efficiency improvement of more than two percent.”
Even more surprising? Hofer linked sleeping with a partner’s shirt to be as effective as taking melatonin, a supplement commonly used to help prepare the body for sleep. “We saw an effect similar in size to what has been reported from taking oral melatonin supplements—often used as a sleep aid,” she revealed.
“One of the most surprising findings is how a romantic partner’s scent can improve sleep quality even outside of our conscious awareness,” added 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.”
It might sound strange, but previous research conducted by Hofer and Chen found that smelling a partner’s scent can help relieve stress, helping to instantly lower levels of cortisol (the stress hormone) upon getting a whiff of that familiar, unique scent you know and love so much. It seems that being able to sniff your romantic partner—even when they’re not there—can promote a feeling of safety, security, and relaxation.
The research is slated for publication in Psychological Science, and researchers are working on further exploration between the power of scent on our quality of z’s. Next up: they’re looking at whether or not infants experience the same calming benefits when exposed to the scent of their parents at night.
As for now, you might want to keep your partner’s favorite tee nearby when you’re sleeping solo—you might just enjoy a more peaceful night’s sleep having it close by than by having your actual partner there, stealing sheets or keeping you up with their snoring.