Sleep masks are one of the simplest sleep accessories there are. But do they actually help? Here is what we know about darkness, sleep and eye masks, without exaggeration.
Why darkness matters for sleep
The body's internal clock responds to light. Darkness in the evening supports the natural release of melatonin, a hormone involved in regulating the sleep-wake cycle. Light at night, even at low levels, can disturb this rhythm. That is why health organisations such as the CDC recommend keeping the bedroom dark.
Where does light at night come from?
Very few bedrooms are completely dark. Common sources are:
- street lights and car headlights
- standby LEDs on TVs, chargers and smoke detectors
- early morning sunlight, especially in summer
- light from hallways or a partner reading
- hotel rooms, trains and planes when travelling
What studies say about sleep masks
A 2023 study published in the journal Sleep (Greenfield et al.) found that young adults who wore an eye mask overnight performed better on a memory task and were more alert the next day than after nights wearing a mask that let light through.
Studies in intensive care units, where light and noise are hard to avoid, have also found that eye masks, alone or combined with earplugs, can improve how patients rate their sleep (Locihová et al., 2018).
Research on sleep masks in everyday life is still limited, and results vary from person to person. But the evidence suggests that blocking light can be a simple, low-cost step towards better rest.
Who benefits most from a sleep mask?
- people whose bedroom cannot be fully darkened
- shift workers who sleep during the day
- frequent travellers
- people who share a room with someone who reads late or gets up early
- anyone who likes to nap during the day
What to look for in a sleep mask
A good sleep mask blocks light completely without pressing uncomfortably on the eyes. It should have an adjustable strap and a soft, breathable fabric. Many people prefer silk for its smooth feel. A lightly weighted mask sits securely and comfortably on the face.
FAQ
Is it healthy to sleep with a sleep mask every night?
For most people, wearing a comfortable, clean sleep mask every night is fine. Make sure it does not press on your eyes and wash it regularly.
Can a sleep mask replace blackout curtains?
A sleep mask blocks light right at your eyes, so it works anywhere. Blackout curtains darken the whole room. Many people combine both.
Do sleep masks help with sleep disorders?
A sleep mask is a comfort product, not a treatment. If you have ongoing sleep problems, please speak to a doctor.
Read more in our guide Why Darkness Matters for Sleep or discover the VALDORÉ Weighted Silk Sleep Mask.