The Importance of Darkness for Sleep: Benefits of Eye Masks

Darkness is as essential to good quality sleep as light is for wakefulness and alertness in the daytime. Levels of melatonin, the body’s natural sleep hormone, rise as light levels fall during the early evening, signalling to the body and brain that it is time to sleep. Excess light levels during the evening and at night time disturb this natural rhythm, delaying the onset of sleep, and disturbing sleep during the night. The Great British Sleep Survey found that 19% of UK adults reported being disturbed by light levels before or during sleep.

Eye masks, which are designed to block out intrusive light during the night, can help ensure light exposure overnight is minimised and thereby may improve sleep.

Studies in hospital inpatients, who often experience high levels of light intrusion overnight, have shown that wearing an eye mask reduces the time taken to fall asleep; increases sleep duration, reduces the number of awakenings at night, and improves sleep quality. For individuals who find that even low levels of light can disturb their sleep, those who work shifts and need to sleep during the daytime, or for those who are travelling across time zones, eye masks can be invaluable in improving sleep quality and duration.

How should you choose your eye mask? The most important feature of course is that it is comfortable and eliminates light! However, some eye masks also incorporate other features, such as fragrance, cooling or warming, and these features can create a feeling of calm, aiding relaxation and winding down to sleep.