If you’ve spent any time sleeping with a partner, you can probably name some of the benefits. Nighttime cuddles, for one thing, and a sense of closeness and intimacy. It can also be reassuring to know that, should an emergency happen during the night, you’ll be there for each other.

Turns out, science backs up these and other potential benefits Dr Ken Sith, President of the American Sleep and Breathing Academy, says, “A growing amount of evidence shows that couples who sleep together not only remain together, but actually extend their lives.”

Smith lists three reasons why this is the case:

  • Stronger relationships. “Sleeping with a significant other increases oxytocin, a chemical that is produced in the same part of the brain that controls your sleep-wake cycle,” Smith says. “Sharing a bed can also help one to feel more connected in their relationship, lowering the risk for developing depression or other mood disorders.”
  • Safety in numbers. “Sleeping next to the one you love produces feelings of protection, safety and security,” Smith says. “These feelings and emotions decrease our anxiety level and lower the body’s level of cortisol, the stress hormone, to allow for more peaceful and restorative sleep.”
  • Good health. “People with healthy and consistent sleep habits are less likely to become sleep deprived,” Smith says. “Over the long term, sleep deprivation can lead to serious conditions including heart disease, obesity, sleep apnea, and insulin resistance – not to mention fatigue, slower reaction times, a compromised immune system, and irritability.”

Per a variety of studies, here are several other potential upsides of sleeping with a partner:

  • Increased REM sleep. One study found that (heterosexual) couples who sleep together enjoyed about 10% more REM sleep as well as less fragmented REM sleep compared to people who sleep solo. Among other critical functions, REM sleep is essential for memory formation. For that reason, one of the study’s researchers concluded that “sleeping with a partner might actually give you an extra boost regarding your mental health, your memory, and creative problem-solving skills.”
  • More sleep overall. A study found couples who sleep together might not only get more REM sleep; they might enjoy more sleep overall. Couples in the study also demonstrated fewer sleep disruptions and were more likely to fall asleep faster compared to single sleepers.
  • Lower blood pressure. A study suggested couples who demonstrate high levels of “sleep-wake concordance” (i.e. couples who are awake and asleep at approximately the same times throughout the night) may experience lower blood pressure and reduced inflammation overall. This could lower the risk of cardiovascular disease.
  • Greater chance of diagnosis. It’s very common for someone to suffer from a sleep disorder such as sleep apnea without even realizing it. Oftentimes, a sleep partner notices the symptoms first, which can prompt the person with those symptoms to seek treatment.
  • Healthier routines. Healthy couples may encourage healthy sleep habits — such as going to bed at a reasonable hour, exercising regularly (which is linked with better sleep), and sustaining treatments for any sleep disorders that might be present in one or both partners. This can have a positive impact on sleep quality and quantity.