For the average person, sleeping with covers pulled up to the ears, wearing pyjamas or night gown is the norm. They sleep fully clothed as if there’s a party to attend in the sleep world!
Yet, sleep scientists advise that, for sleep to be restorative, our bodies need to be cool. In other words, when you sleep fully clothed or covered, your body gets warm, perhaps too warm for comfort.
Researchers explain that body temperature goes down while we sleep by about two degrees, noting that it’s like going into ‘energy saving mode’. “Sleeping naked makes it easier to regulate temperature and get to that optimal point,” researchers say.
While experts agree that the merits of sleeping nude, compared to wearing pyjamas or night gown in bed haven’t been studied extensively, some research shows benefits to sleeping naked.
“Overheating to the point of sweating because of synthetic, uncomfortable pyjamas will wake you up during the night,” says certified somnologist Dr Ana Brito from the European Sleep Research Society.
However, if you insist on wearing pyjamas or night gown to bed, Dr Guy Meadows of Sleep School says it isn’t necessarily the worst thing to do.
If you want to sleep more deeply, staying cooler by sleeping naked or in a cold room will help
“Sleeping naked has benefits such as regulating body temperature, preventing overheating and offering a less restrictive and more comfortable experience.
“On the other hand, sleeping in pyjamas can provide insulation, particularly in colder climates. Find what feels comfortable, considering factors like body temperature preferences and climate,” Dr. Meadows counsel.
Benefits of sleeping nude
Generally speaking, for the body to be able to properly release melatonin [the hormone that brings on sleep and keeps us unconscious through the night], it needs to be cool.
Release of melatonin
“If you’re too hot while you’re trying to sleep, your body won’t release as much melatonin, so you’ll find it harder to get to sleep and stay asleep,” says Sammy Margot, a chartered physiotherapist and sleep expert. “If you want to sleep more deeply, staying cooler by sleeping naked or in a cold room will help.”
Margot notes that everyone will have a different set point at which they start feeling the cold. If you grew up in a warmer climate, you’ll feel the cold more than someone who is used to a temperate climate. However, just like with cold-water bathing or wild-swimming, you can gradually expose yourself to cooler temperatures that should help you sleep.
When your body is in deep sleep, it can start restorative work, repairing damaged cells
Increased anti-ageing hormones
Once your body is in deep sleep, it can start restorative work, repairing damaged cells. It does this by releasing Human Growth Hormone (HGH).
HGH can reverse signs of ageing by restoring cells in the skin, hair, muscles, bones, and other tissues. It also reduces blood pressure and could boost your workout. A 2011 study from Stanford University found that higher amounts of HGH from better sleep improves athletic performance.
Not getting enough sleep, perhaps through being too hot in bed, impedes the release of HGH. Researchers at Warwick University found that those who sleep for less than six hours each night are three times as likely to develop type 2 diabetes or heart disease. This is because cortisol, the stress hormone, and ghrelin, the hunger hormone, both surge so you’ll be more tempted to eat and have poorer control over your appetite when you do.
Genital health
“There’s evidence to suggest that women who sleep naked are less likely to develop yeast infections,” says Margot. “You need adequate air circulation to prevent candida, a natural yeast, from flourishing in the vagina. You tend to see women who wear tight or synthetic underwear or bedwear which doesn’t allow much airflow developing these conditions.
women who sleep naked are less likely to develop yeast infections
“For men, there was a 2015 study from Stanford University which found men who go nude at night had 25 per cent less DNA fragmentation in their sperm compared with men who wore tight briefs day and night,” adds Margot. “We know men who keep their testicles cool have better sperm quality. Wearing underwear to bed increases the temperature of the scrotum which can decrease sperm vitality and count.”
Happier relationships
“Sleeping naked with a partner may increase connection,” says Margot. “Evidence suggests that partners who spend time in skin-to-skin contact release more oxytocin, the hormone associated with love that makes you feel good. It can also help to reduce anxiety, so that will also improve your sleep.”
Higher levels of oxytocin also have positive effects on sexual responsiveness and some research shows it can improve orgasms too.
Even for singletons, there’s a benefit to spending more time without clothes. A study from Goldsmiths University found that being nude improves self-esteem.
men who go nude at night had 25 per cent less DNA fragmentation in their sperm
What if you really don’t want to sleep naked?
If you don’t want to sleep naked, choose nightwear made with natural fibres. “Linen, bamboo, or silk,” advises Dr Lindsay Browning, neuroscientist and sleep expert.
“These fabrics will wick off sweat and keep you dry and cool at night. This will be particularly important for women suffering from night sweats in the menopause,” Dr. Browning said.
