Your bedroom may feel dark enough, but your sleeping brain keeps listening for light. Could a simple eye mask change how your night unfolds?
Study at a glance
- Study: Hu RF, Jiang XY, Zeng YM, Chen XY, Zhang YH. Effects of earplugs and eye masks on nocturnal sleep, melatonin and cortisol in a simulated intensive care unit environment. Critical Care, 2010;14(2):R66.
- Design: 14 healthy volunteers underwent polysomnography (sleep-lab recording) across four conditions: adaptation, baseline, simulated ICU noise and light, and simulated ICU noise and light with earplugs and eye masks.
- Measures: sleep stages and arousals, plus urinary melatonin and cortisol.
What the research shows
According to the published report, when participants wore earplugs and eye masks during the simulated ICU environment, they showed more REM sleep time, shorter REM latency (the time to reach REM), fewer arousals and higher melatonin levels than when exposed to the noise and light without them. The authors concluded that earplugs and eye masks may promote sleep and hormone balance in healthy people exposed to simulated ICU noise and light.
Some honest caveats: the sample was small (14 people), participants were healthy volunteers rather than patients, the setting was a simulated ICU (much brighter and noisier than a typical bedroom), and the intervention combined both earplugs and eye masks, so the effect of the mask alone cannot be separated from this study. Later research in real ICU patients has been mixed on some outcomes, so this is encouraging evidence, not proof of a guaranteed effect.
Why it may work
Light is the body's main timing signal. Light reaching the eyes, even through closed eyelids, can influence the brain's internal clock and is known to suppress melatonin, the hormone associated with the onset of night. By blocking light, an eye mask may help keep the environment closer to true darkness, which in turn may support the natural nighttime melatonin rise. Less light and noise may also mean fewer brief awakenings.
Real-world use
Most of us are not in an ICU, but many of us sleep with streetlights, a hallway glow, standby LEDs, early sunrise or shift-work daylight. Travel adds hotel curtains that never quite close and flights with cabin lights. In these everyday situations, a mask is a simple, low-effort way to make your sleep environment darker.
Where the Gudslip Blindfold fits
The Gudslip Blindfold is designed to block out light so your eyes are in darkness while you sleep or nap. We share the study because it explores the same mechanism, reducing light exposure at night, not because the Blindfold has been tested in that trial. It is a comfort and sleep-environment tool, not a treatment for any condition, and individual results vary.
How to use it
- Put the mask on 10 to 15 minutes before lights-out as part of a wind-down routine.
- Adjust the strap so it sits snugly over your eyes without pressing on them.
- Pair it with other sleep-friendly habits: a cool room, a regular schedule and screens off before bed.
- Give it a week or two to get used to the feeling before judging the effect.
FAQ
Does an eye mask increase melatonin?
In the study above, melatonin levels were higher with earplugs plus eye masks than without them in a simulated ICU. That does not show a mask alone raises melatonin in a normal bedroom.
Can I wear it for naps and travel?
Yes. A mask is easy to pack and may help in bright or unfamiliar environments.
Is complete darkness necessary?
Not for everyone, but lower light at night is generally considered supportive of healthy sleep. Try it and see how you feel.
What if I still sleep poorly?
Persistent sleep problems can have many causes. Speak with a healthcare professional.
The bottom line
A small, real sleep-lab study found that blocking light and noise with earplugs and eye masks was associated with more REM sleep, fewer arousals and higher melatonin in a simulated ICU. It is promising, but limited, and it points to a simple idea: protect your darkness. An eye mask is an easy way to try it.
Disclaimer: This article is for general wellness and educational purposes only and is not medical advice. Gudslip products are not intended to diagnose, treat, cure or prevent any disease. Please consult a healthcare professional about any sleep concerns.
References
- Hu RF, Jiang XY, Zeng YM, Chen XY, Zhang YH. Effects of earplugs and eye masks on nocturnal sleep, melatonin and cortisol in a simulated intensive care unit environment. Crit Care. 2010;14(2):R66. doi:10.1186/cc8965. https://ccforum.biomedcentral.com/articles/10.1186/cc8965