Yes, sleep masks can help you sleep, especially if your bedroom is not fully dark. Light reaching your eyes at night suppresses melatonin, the hormone that signals night-time. Studies link wearing a mask with better sleep in bright, noisy settings and with better memory and alertness the next day, though masks are not a cure for insomnia.
This article explains how light affects melatonin and sleep, what the research on eye masks actually found, who gets the most from one, and what to look for when you choose a mask.
Key takeaways
- Ordinary room light in the evening delayed melatonin in 99% of people in one large lab study and shortened their melatonin night by about 90 minutes.
- One night of moderate light during sleep raised night-time heart rate and lowered heart rate variability in healthy adults.
- In a 2023 study of young adults, a week of wearing an eye mask improved learning and alertness compared with a week without one.
- Masks help most when you cannot make your room dark: summer mornings, streetlights, shift work, travel or a partner's reading light.
- Choose a mask that blocks light without pressing on your eyes, and give yourself a few nights to get used to it.
How does light affect sleep and melatonin?
Your body clock uses light as its main signal for day and night. When it gets dark in the evening, your brain releases melatonin, a hormone that tells your body it is night. Light, including ordinary indoor lighting, holds that signal back.
A 2011 study by Gooley and colleagues in the Journal of Clinical Endocrinology and Metabolism showed how strong this effect is. Researchers compared 116 healthy adults aged 18 to 30 living in room light or dim light in the 8 hours before bed. Compared with dim light, room light before bedtime:
- delayed the start of melatonin release in 99% of participants
- shortened the time melatonin was present by about 90 minutes
Room light during the usual hours of sleep also suppressed melatonin by more than 50% in most of the test sessions.
Light during sleep affects more than melatonin
Light while you are asleep seems to matter too. In a 2022 study in PNAS by Mason and colleagues, 20 healthy adults slept one night in moderate light (100 lux) and another in dim light (under 3 lux). After the lit night, they had a higher night-time heart rate, lower heart rate variability and higher insulin resistance the next morning.
That was one night in a lab, so it does not prove long-term harm. It does show that your body notices light at night even when you are asleep. Heart rate and HRV are both signals a sleep tracker records, which is one reason a dark room can show up in your overnight numbers.
What does the research say about sleep masks?
Masks and next-day memory and alertness
The best study on healthy people sleeping at home is a 2023 paper in the journal Sleep by Greco and colleagues. In the first experiment, 94 adults aged 18 to 35 wore an eye mask every night for a week and spent another week with light not blocked. After the mask week, they did better at learning new information and on an alertness test.
In a second experiment, 35 people wore a sleep-monitoring headband with and without the mask. The learning benefit came back, and it was linked to the time spent in slow-wave (deep) sleep. The mask did not change total sleep time or the overall structure of the night.
So the honest summary is this: in young, healthy sleepers, a mask did not add sleep, but it seemed to make the sleep they got more useful for the next day. If you want more on why deep sleep matters, see our guide to sleep stages explained.
Masks in bright, noisy environments
Much of the earlier research comes from hospital intensive care units, where light and noise run all night. In a 2010 study in Critical Care by Hu and colleagues, 14 healthy volunteers slept with recorded ICU noise and light. Wearing earplugs and an eye mask gave them more REM sleep, fewer arousals and higher melatonin levels than sleeping in the same conditions without them.
A 2015 Cochrane review of ways to improve sleep in intensive care found some evidence that earplugs, eye masks or both may help sleep in ICU patients, but rated the quality of that evidence as low.
What the evidence does not show
- Most studies are small, short, or done in hospitals and labs rather than normal bedrooms.
- Several tested masks together with earplugs, so the mask's own effect is hard to separate.
- There is no good evidence that a mask treats insomnia or any sleep disorder.
Who benefits most from a sleep mask?
A mask does the most for people who cannot get their room properly dark. Cleveland Clinic's sleep specialists point to a similar list:
- Shift workers who sleep during the day.
- Anyone without blackout curtains or blinds, particularly in summer, when UK sunrise can come before 5am.
- People living near streetlights or with light leaking under the door.
- Travellers in hotel rooms, on trains or on planes.
- Partners on different schedules, where one reads or uses a phone in bed.
- People who wake early and find it hard to get back to sleep once it is light.
The NHS advice on insomnia includes making sure your bedroom is dark and quiet, using curtains, blinds, an eye mask or earplugs if needed. A mask is one tool on that list, not a replacement for the rest.
Sleep mask or blackout curtains?
| Sleep mask | Blackout curtains or blinds | |
|---|---|---|
| Blocks light | At the eyes, wherever you are | For the whole room, if they fit well |
| Travel | Goes with you | Stays at home |
| Partner's light | Blocks it | Does not help |
| Comfort | Takes a few nights to get used to | Nothing to wear |
| Light leaks | Can leak at the nose if the fit is poor | Can leak at the edges and top |
Many people use both: curtains for most of the room and a mask for the gaps.
How to choose a sleep mask
- Check the seal. Light sneaking in around the nose defeats the point. Try it on in a lit room and look up and down.
- Avoid pressure on your eyes. Flat masks press fabric on to your eyelids. Contoured masks have shaped cups so the fabric sits clear of the eyes, which many people find more comfortable.
- Look at the strap. It should hold the mask in place when you roll over without feeling tight.
- Think about side sleeping. A slimmer profile is easier against a pillow.
- Keep it clean. Wash it as the maker instructs, because it sits on your skin every night.
- Consider noise too. If sound wakes you as well, earplugs used with the mask cover both.
Peak Blackout is a contoured blackout mask with moulded eye cups, so nothing presses on your eyes. It costs £29.99.
How to get used to wearing a sleep mask
Most people need a few nights to stop noticing a mask. Put it on as part of your wind-down, not the moment you switch the light off. If it slips off in the night, adjust the strap rather than tightening it hard.
Judge it over a couple of weeks rather than one night, and change one thing at a time. If you also cut back on late caffeine in the same week, you will not know which change helped. Our guide on caffeine and sleep explains how to test that separately, and the 14-night sleep experiment sets out the whole method, with a log you can copy. A sleep tracker such as PulseRing Pro, which records sleep stages, heart rate and HRV each night, can help you compare the two weeks, alongside the simplest measure of all: how you feel in the morning.
When a sleep mask will not fix the problem
If you are lying awake most nights, waking unrefreshed however long you sleep, or your partner notices loud snoring or pauses in your breathing, a mask is not the answer. Those can be signs of insomnia or a condition such as sleep apnoea. Speak to your GP.
Frequently asked questions
Is it OK to wear a sleep mask every night?
For most people, yes. In the 2023 study published in Sleep, participants wore a mask every night for a week, and the NHS lists an eye mask among its tips for a dark bedroom. Choose one that does not press on your eyes, keep it clean, and stop using it if your eyes or skin become irritated.
Do sleep masks increase melatonin?
A mask does not add melatonin, but it can stop light from suppressing it. Light is the main signal that holds melatonin back, and room light during normal sleep hours suppressed melatonin by more than half in most sessions of one lab study. In a small simulated intensive care study, earplugs and eye masks together led to higher melatonin levels.
Do sleep masks help with deep sleep or REM sleep?
The evidence is limited. In the 2023 study, a mask did not change the overall structure of sleep, but the next-day learning benefit was linked to time in deep sleep. In a small study with simulated hospital noise and light, earplugs and a mask together increased REM sleep. Neither shows a large change in a normal dark bedroom.
Are contoured sleep masks better than flat ones?
There are no studies comparing them directly, so it comes down to comfort and fit. Contoured masks have shaped cups that keep fabric off your eyelids, which many people prefer, especially if flat masks feel like they press on the eyes. Whichever style you choose, a good seal around the nose matters most for blocking light.
Should I use earplugs with a sleep mask?
If noise wakes you as well as light, yes. Several of the studies on masks tested them together with earplugs, particularly in noisy hospital settings, and the NHS suggests an eye mask or earplugs as needed for a dark, quiet bedroom. If light is your only problem, a mask on its own is enough.
Sources
- Gooley JJ et al. Exposure to room light before bedtime suppresses melatonin onset and shortens melatonin duration in humans, Journal of Clinical Endocrinology and Metabolism, 2011
- Mason IC et al. Light exposure during sleep impairs cardiometabolic function, PNAS, 2022
- Greco V et al. Wearing an eye mask during overnight sleep improves episodic learning and alertness, Sleep, 2023
- Hu RF et al. Effects of earplugs and eye masks on nocturnal sleep, melatonin and cortisol in a simulated intensive care unit environment, Critical Care, 2010
- Hu RF et al. Non-pharmacological interventions for sleep promotion in the intensive care unit, Cochrane Database of Systematic Reviews, 2015
- Do Sleep Masks Help?, Cleveland Clinic, 2026
- Insomnia, NHS, 2024
This article is for general information and is not medical advice. PulseRing Pro is a wellness device, not a medical device, and does not diagnose or treat any condition. If you are worried about your health, speak to your GP or a qualified clinician.
