What Lack of Sleep Does to Your Skin and Hair, Night by Night

Lack of sleep does show on your skin, mostly around your eyes, and strangers can spot it after a single short night. For hair, the case that short nights cause shedding is thin, and it comes from records of diagnosed sleep disorders.

If you've had a week of five-hour nights and your face looks flat and heavy-lidded, you're not imagining it. What you probably want to know is whether that's a bad week or damage that builds up. The studies answer those two questions very differently, and they were done on very different people.

What Does One Bad Night Do to Your Face?

It mostly changes your eyes. In a Stockholm lab study, 10 volunteers (five of them women) were photographed after normal sleep. They were photographed again after 31 hours awake, following a night of only 5 hours.

Forty observers then rated the photos. The sleep-deprived faces had more hanging eyelids, redder and more swollen eyes, and darker circles. Their skin looked paler, with more wrinkles or fine lines, and the corners of their mouths drooped. Rashes and eczema didn't change.

A second Swedish study used 23 volunteers aged 18 to 31. The 65 observers judged the sleep-deprived faces as less healthy, less attractive and more tired.

Both studies measured what other people see the next afternoon. Neither one looked at your skin's structure or whether anything lasts.

Two Short Nights and People Notice

You don't need to pull an all-nighter for it to show. A later Swedish study photographed 25 people (14 women, aged 18 to 47). Each was photographed after normal sleep and after two days of restricted sleep.

The 122 raters found the sleep-restricted faces less attractive, less healthy and sleepier. They were also less willing to socialize with them. Trustworthiness ratings didn't change, which is a small mercy.

What a Week of Short Sleep Did to Skin

A Korean study is the closest thing to your bad week, though it went harder than most. It followed 32 Korean women in their 40s for two weeks, with smartwatches tracking their sleep.

For six nights they slept 8 hours. For the next six they slept 4. Skin hydration dropped after one day of short sleep and kept falling. Gloss, flaking, elasticity and wrinkles also got worse from the first day, and texture by the fourth.

Elasticity was hit hardest. Four hours a night is far less than most people's rough patch, so treat this as the outer edge of what a short week can do.

Does Poor Sleep Age Your Skin Over Time?

Possibly, but the best study is small, and two of its authors worked for a beauty company. Researchers at University Hospitals Case Medical Center in Cleveland compared 60 healthy white women. Half were poor-quality sleepers getting 5 hours or less, and half were good sleepers getting 7 to 9 hours.

The poor sleepers had more signs of intrinsic aging, the kind that comes with time rather than sun. Their skin lost more water at rest. After tape was used to strip the outer layer, the good sleepers' barrier had recovered 30% more by 72 hours.

Good sleepers also recovered better from redness 24 hours after a dose of simulated sunlight. And they rated their own looks more kindly. The difference in outward (extrinsic) signs of aging, such as sun damage, wasn't statistically significant.

Those two authors worked for Estée Lauder. The study compared two groups at one point in time, so it shows a link, not that sleep caused the aging. Poor sleepers may differ in other ways, like stress.

Does Lack of Sleep Make Your Skin Darker?

It can make the skin under your eyes look darker, but not in the way most people think. First, look at who was in the studies above.

The aging study enrolled only white women. The week-long study enrolled only Korean women. The Swedish photo studies measured how strangers read a tired face, not what happens in the skin.

That gap matters most for dark circles. Cleveland Clinic lists people with darker skin tones among those more likely to have dark circles. Older adults and anyone whose family has them are on the list too. Its causes include genetics and extra melanin from sun, not only fatigue.

When you're short on sleep, Cleveland Clinic says, the skin under your eyes can look paler, so blood vessels show through more. Cleveland Clinic suggests at least seven hours a night to help prevent shadows. Their color can range from blue or purple to brown or black depending on your skin tone.

More sleep won't fade darkness caused by extra pigment from the sun. A simple stretch test for under-eye darkness tells you which kind you have.

Does Lack of Sleep Cause Hair Loss in Women?

The evidence for everyday short sleep is thin. A large Korean study looked at diagnosed sleep disorders and patchy hair loss, not tiredness and shedding.

It used national health insurance records from 2003 to 2013. People with a sleep disorder (25,800 of them) were compared with 129,000 matched people without one. The sleep disorder group was about 1.65 times as likely to develop alopecia areata. That's the autoimmune kind that leaves round bald patches, and the link was strongest under 45.

That's an association in records, not proof. If your hair is coming out all over after a hard few months, the stress itself may be the cause. Stress hair loss usually starts months later, which is why the timing fools people.

What Your Pillow Does to Your Hair Overnight

The clearer overnight effect on hair is friction. For curly hair, the American Academy of Dermatology says rubbing against your pillowcase can make hair frizzy and easier to break. It suggests a loose ponytail on top of your head, or a loose braid.

The AAD adds that twists, and satin or silk bonnets or pillowcases, may also reduce friction. Whether a silk or satin pillowcase is worth it over a bonnet is a separate question about fit and cost.

How Much Sleep Do You Need for Your Skin?

Aim for at least 7 hours. The CDC recommends 7 or more hours a night for adults aged 18 to 60. The good sleepers in the Cleveland skin study got 7 to 9.

The Cleveland study didn't test 6 hours, so don't read the 5-hour results onto a 6-hour habit. What the research does support is simple. Protect your hours most weeks, and expect a bad night to show mainly around your eyes the next day.

If you wake at 3 a.m. and can't drop off again, start with what keeps night waking going.

When to See a Doctor

The CDC says to talk to your provider if you have problems sleeping. Some conditions stop you getting good sleep no matter how hard you try.

Sleep apnea is one to rule out. Mayo Clinic's list of common sleep apnea symptoms includes loud snoring, gasping for air and breathing that stops (noticed by someone else). It also lists waking with a dry mouth, morning headaches and excessive daytime sleepiness. Not everyone with sleep apnea snores.

Mayo Clinic says to talk to your healthcare professional if you have these symptoms, or any sleep problem that leaves you very tired, sleepy or irritable.

For hair, Mayo Clinic says to see a doctor if you notice sudden or patchy hair loss, which can signal a condition that needs treatment. The same goes for more hair than usual coming out when you comb or wash it. If your hairline is receding, Mayo Clinic says to ask about early treatment. For your eyes, Cleveland Clinic says to call a provider if a dark circle or swelling appears under just one eye.

Frequently Asked Questions

Is Beauty Sleep Real?

Yes, in the sense that other people can see it. In the Swedish studies, strangers rated sleep-deprived faces as less healthy and less attractive. Whether short sleep ages skin for good is much less certain.

Is 6 Hours of Sleep Enough for Your Skin?

Probably not ideal. The CDC recommends 7 or more hours for adults up to 60. The Cleveland skin study compared 5 hours or less with 7 to 9, so 6 hours wasn't tested.

Why Do I Look Tired Even After a Full Night's Sleep?

Your dark circles may not be about sleep at all. Cleveland Clinic lists genetics, aging and pigment as causes, and dark circles are more common on darker skin. Sleep won't fade pigment.