SCIENCE OF SLEEP
Why darkness matters.
Your body was built to sleep in the dark. Here is the simple science behind it, and how a sleep mask helps you improve the quality of your sleep.
Shop the Layali collectionDarkness tells your body it's time to rest.
Your body runs on an inner clock. Light keeps it in "day mode." When the world goes dark, your body starts making melatonin, the hormone that helps you feel sleepy and stay asleep.
Lights go down
Your eyes notice the change in light and send a message to your brain's inner clock.
Melatonin rises
In the dark, your body releases melatonin. You start to feel calm, slow and ready for bed.
Sleep runs smoothly
With steady darkness, your body can move through light, deep and dream sleep through the night.
Even a little light makes a difference.
Streetlights, screens and standby LEDs all reach your eyes, even through closed eyelids.
Ordinary room light in the evening shortened the body's melatonin window by about 90 minutes.
Gooley et al., 2011Just one night sleeping with a dim overhead light raised heart rate during sleep in healthy adults.
Mason et al., 2022People who wore an eye mask and earplugs in a bright, noisy room got more dream sleep.
Hu et al., 2010Simple darkness, studied seriously.
Scientists have tested eye masks in sleep labs and hospitals, two places where light and noise make rest hard.
Eye masks helped people learn and stay alert.
Adults who wore an eye mask overnight did better on memory tests and reacted faster the next day than when they slept with light let through.
Read the studyMasks and earplugs supported natural melatonin.
In a room set up to feel like a busy hospital ward, people wearing an eye mask and earplugs had more dream sleep, woke less, and kept higher melatonin levels.
Read the studyA review of hospital studies agrees.
Researchers pooled many trials in intensive care and found that eye masks and earplugs were linked to better sleep quality for patients.
Read the reviewEvening light delays your sleep hormone.
Normal indoor lighting before bedtime pushed back the start of melatonin and shortened how long it lasted through the night.
Read the studyYour own darkness, anywhere.
Blackout curtains stay at home. A mask goes wherever you sleep.
Total darkness
Blocks streetlights, early sunrise, screens and the glow of a partner's phone.
Drift off sooner
Darkness is a clear cue for your body to wind down, so falling asleep can feel easier.
Stay asleep
Less light means fewer small wake-ups when the room brightens at dawn.
Wake up fresher
Better quality rest can help you feel sharper and more alert the next day.
Made for travel
Flights, hotels, night shifts and afternoon naps. Your sleep comes with you.
Calm your eyes
A soft, contoured mask rests gently around your eyes and signals the end of the day.
Six small habits for deeper sleep.
Good sleep is a skill. These simple steps help your body get the message that night has arrived.
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1 hour beforeDim the lightsSwitch to lamps and warm, low light around the house.
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30 min beforePut the screens awayPhones and laptops give off bright light that keeps your brain alert.
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BedroomKeep it cool and quietA cool room, around 18 °C (65 °F), suits most sleepers.
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Lights outMask on, last stepMake your mask the final cue of the day. Same time, every night.
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MorningGet daylight earlyBright light soon after waking helps set your clock for the night ahead.
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Every dayKeep a steady wake timeWaking at the same time, even on weekends, keeps your rhythm strong.
Own your sleep.
Bring the darkness your body needs, wherever you rest. Discover the Layali collection.
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