Blue-Light Glasses: Do They Help With Sleep or Eye Strain?

Short answer: Blue-light glasses probably won't do much for tired eyes, and whether they help you sleep is still unclear. A 2023 Cochrane review of 17 randomized trials found they may not reduce eye strain from computer use, and the sleep studies were small with mixed results. [S01] The American Academy of Ophthalmology (AAO) does not recommend blue-light glasses. [S02] For better sleep, the more reliable steps are cutting back on screens in the two to three hours before bed and using your devices' night settings. [S02]

Blue-light glasses are marketed for eye comfort, better sleep and even long-term eye protection. Here is what the research says about each claim, and what eye doctors and sleep experts suggest instead, whether you are at home or spending evenings in a hotel room before an appointment.

What blue-light glasses claim to do

Blue-light filtering lenses block ultraviolet light and some of the short-wavelength visible light, often called blue light, from reaching the eye. [S01] Sellers make three main claims: that they improve visual comfort with digital devices, protect the retina and improve sleep quality. [S01]

The AAO says ads for these glasses claim that too much blue light can cause digital eye strain, disrupt sleep or even lead to blinding eye diseases. [S03] The evidence for each claim is different, so it helps to take them one at a time.

The best evidence: a 2023 Cochrane review

The 2023 Cochrane review of blue-light filtering lenses included 17 randomized controlled trials with between five and 156 participants each, and graded how certain the evidence was for each outcome. [S01] Follow-up periods were short, from less than a day to five weeks. [S01] None of the trials had a low risk of bias across all the areas the reviewers checked. [S01]

Here is what the reviewers found for each outcome:

Side effects were reported only occasionally. They included headache, discomfort wearing the glasses, lower mood and increased depressive symptoms. [S01] The reviewers called for better-quality trials on vision, macular health and sleep. [S01]

Do blue-light glasses help you sleep?

The honest answer is that nobody knows yet. The six sleep trials in the Cochrane review had 148 participants in total and studied very different groups, from healthy adults to people with mental health and sleep disorders. [S01] Half reported better sleep scores with blue-light filtering lenses and half found no difference, so the reviewers rated the sleep evidence as very low certainty. [S01]

What is better established is that light timing matters. The AAO explains that blue light affects the circadian rhythm, the body's natural sleep-wake cycle. [S02] During the day, blue light helps wake us up, but too much exposure late at night from a phone, tablet or computer can make it harder to fall asleep. [S02] The National Heart, Lung, and Blood Institute (NHLBI) adds that bright artificial light from a TV or computer screen before bed may signal the brain that it's time to be awake. [S05]

That is why the AAO's sleep advice focuses on when you use screens, not on special lenses. [S02]

Do they help with eye strain?

Probably not, according to both the Cochrane review and the AAO. The AAO says several studies suggest blue-light blocking glasses do not improve the symptoms of digital eye strain. [S02] The academy also says there is no scientific evidence that blue light from digital devices damages the eyes. [S02]

The tired, dry, achy feeling after a long day of screens is usually digital eye strain, which the AAO links to how we use screens rather than to the light they give off. [S03] People normally blink about 15 times a minute, but only about 5 to 7 times a minute while using a computer or other digital device. [S04] Blinking less leaves the surface of the eye drier. [S04] The AAO says eye strain does not cause lasting damage. [S02]

Is blue light from screens harmful?

The AAO says the largest source of blue light is sunlight, and screens give off much less. [S02] Blue light from screens is also no more damaging than blue light from the sun, according to an AAO spokesperson. [S02] Because there is no evidence that screen light is damaging, the AAO does not recommend any special eyewear for computer use. [S03] The academy notes that the amount of light coming from a computer has never been shown to cause any eye disease, and that a study found no measurable UVA or UVB radiation from computer screens. [S03]

Blocking blue light may not be risk-free either. Some studies suggest that too little sunlight in childhood could affect how children's vision develops, and a recent study suggests that not getting enough sun could raise the risk of nearsightedness in teens and young adults. [S02] An AAO spokesperson says that taking preventive measures against blue light when there is no evidence of damage could be more harmful than the blue light itself. [S02] For children who use screens all day, the AAO's advice is the same as for adults: take breaks. [S03]

What eye doctors recommend instead

For eye strain, the AAO suggests these habits: [S02] [S03]

• Use the 20-20-20 rule. Every 20 minutes, look at something at least 20 feet away for at least 20 seconds.
• Refresh dry eyes with artificial tears.
• Set up your screen. Sit about 25 inches, roughly an arm's length, from the screen and position it so you look slightly downward.
• Fix the lighting. Adjust room lighting, increase screen contrast and use a matte screen filter if glare is a problem.
• Give contacts a break by wearing your glasses some of the time.

The AAO also suggests matching your screen's brightness to the light around you, because a screen that glows brighter than its surroundings makes your eyes work harder. [S04]

If you spend many hours at a computer, prescription computer glasses may help. They are focused for screen distance, about 20 to 26 inches from your face. [S04] The AAO points out that these are not the same as blue-light blocking glasses. [S04]

Most eye symptoms from computer use are temporary and ease after you stop. If they continue, the AAO advises contacting an ophthalmologist. [S03]

Screen habits for better sleep

These steps come from the AAO and NHLBI, and you can use them at home or in a hotel:

• Limit screens in the two to three hours before bed. [S02]
• Turn on night or dark mode on your devices in the evening. [S02] [S03]
• Use the hour before bed for quiet time, and avoid bright artificial light, such as from a TV or computer screen. [S05]
• Keep a regular schedule. Go to bed and wake up at the same time every day. [S05]
• Watch the caffeine. Its effects can last up to 8 hours. [S05]
• Keep the bedroom quiet, cool and dark. A dim night light is fine if you need one. [S05]
• Get outside during the day when you can. [S05]

Our guide to sleeping better away from home covers how to set up an unfamiliar room for sleep. If a clock change is coming up, see how to protect your sleep when daylight saving time ends. For winding down after a busy day, our everyday stress habits guide has simple routines.

The bottom line

The best evidence suggests blue-light glasses may not ease eye strain, and their effect on sleep is unproven. [S01] Regular screen breaks, artificial tears and a screen-free wind-down before bed are better-supported places to start. [S02] [S05]