Inhaling the familiar human smell, we fall asleep better and feel more sleepy in the morning.
The smell of a romantic partner has a positive effect on the quality of sleep - even if that very partner is not sleeping next to you. This is the conclusion reached by psychologists from the University of British Columbia. An article about this will be published in the edition of Psychological Science.
"Our study provides new evidence that sleeping with [inhaling] the scent of the [romantic] partner's body significantly improves sleep quality," said lead author Marlise Hoffer. “We saw an effect comparable to that of oral administration of melatonin (a drug for regulating circadian rhythms. - Ed. Note).”
Scientists conducted an experiment in which 155 people slept using T-shirts as pillowcases. Some of the subjects received clean T-shirts or clothes worn by a stranger. The rest of the participants in the experiment slept on T-shirts that their partner wore for a while. To do this, the "second halves" of the subjects were given clean T-shirts, which they had to wear for 24 hours.
However, it was recommended to refrain from using deodorants and perfumed body products, exercising, smoking and eating foods that can affect body odor. After the partners of the subjects returned the T-shirts to the experimenters, the clothes were stored at freezing temperatures to preserve the aroma.
Each of the participants in the experiment was given two T-shirts, without telling who exactly wore them or whether they wore them at all. The subjects slept for two nights in a row, first on one and then on another T-shirt. Sleep quality was determined using actigraphs (wearable sensors that record human movements). Also, after waking up, the subjects answered questions about their own health and sensations. At the end of the experiment, the participants had to guess if any of the sleeping shirts belonged to their partner.
Subjects reported feeling more refreshed overnight when they believed they were smelling their partner's scent. Regardless, sleep observation data showed that study participants slept better (less tossing and turning and stirring during sleep) when they smelled familiar human scent.
According to the authors of the experiment, the physical presence of a long-term romantic partner during the night's rest is associated with positive health effects, such as a sense of security, calmness and relaxation, and allows for a deeper sleep. The simple scent of a partner can have a similar effect. Scientists are now recruiting participants for a new experiment to see if the smell of parents can improve the quality of their child's sleep.
Promotional video:
Author: Polina Gershberg
