Why Some People Sleep Better With Another Person In Bed

Photographed by Lula Hyers.
Sharing the bed with a partner for the first time can be an important test: Is the person a barnacle who wants to clutch your body until you're both sweating? Do they ghost before the sun rises? Or are they respectful of your physical boundaries and drift into REM sleep an arm's length away? In truth, sleeping with another person is a skill that takes learning. But some people have an easier time adjusting to the new circumstances than others.
"Sleep is very sensitive to the individual's environment," Scott Hollingshaus, MD, clinical instructor of sleep medicine at the University of Utah's Sleep Wake Center told Refinery29 last month in an interview about summer sleep struggles. Each person is acclimated to their individual room's environment, which includes the lighting, noise, bed, and temperature, Dr. Hollingshaus said. Any significant changes in your environment can be disruptive to sleep, which is why the first night of sleep in a new bed — or with a new partner — can be so shoddy. Over time, you might get used to having another body in bed, so that becomes your new norm. But do couples actually sleep better when they're together?
While your sleep environment could make it easier to sleep with another person in bed, there might be some emotional reasons why you sleep better with someone else under the covers. A review of research that ran in the Wall Street Journal in 2012 hypothesized that perhaps sleeping in bed with another person provides feelings of safety and security, which may lead to better sleep.
A small 2017 study examined how well heterosexual couples sleep in bed together. Sleeping together didn't improve the couples' sleep quality or quantity, but both the men and women in the study said their perceived sleep quality was higher when they slept with their partner. And men in particular slept longer and got up later when sleeping with a partner compared to their solo nights. Researchers say that if you're in bed with a person you like and trust, then you'll likely sleep better — or at least feel like you're sleeping better.
From an evolutionary standpoint, these theories kind of make sense: When kids are scared at night, they go to their parents' room to be comforted. In last season of Keeping Up With The Kardashians, Kim Kardashian West told her sisters that she didn't want to sleep alone in a hotel bed in Palm Springs. She was still grappling with the trauma of her robbery a few months prior, and having someone in bed with her was comforting. For some people, the stress from a traumatic event can lead to a slew of sleep issues, so having a trusted friend or family member sleep in the room can help, according to the National Sleep Foundation. So although having another body in bed might not directly impact that person's sleep quality, it could be comforting or help to quell anxiety.
The same rules don't apply for babies, though. The American Academy of Pediatrics advises against co-sleeping, or sleeping with an infant in bed with you. Some co-sleeping advocates claim that babies and parents sleep better when they're in bed together, but the vast majority of experts agree that the danger of a sleep-related death is much too high.
But if you're looking for consensual couple's sleeping? It's usually perfectly safe, even if it can be a little uncomfortable.
Sleep is a very personal process, and it might take some time for you and your partner to sync up. Or you might have to make a few adjustments in the bedroom to make sure that you're both comfortable. But if you are someone who does enjoy having another body in bed, just make sure you find a cuddling position that you and your partner enjoy — and please, don't hog the covers.

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