Do blue light glasses work? What eye doctors and the research say

For eye strain, probably not. The American Academy of Ophthalmology does not recommend blue light glasses for computer use, because the blue light from screens has not been shown to harm the eyes. A 2023 Cochrane review of the trials came to a similar place: blue light filtering lenses may make little or no difference to eye strain, at least over the short periods that were studied.

That doesn't make the glasses harmful, and some people like the way they feel. But the tiredness, dryness and headaches of a long screen day come from how you use the screen, not from the color of its light, and the fixes for that have little to do with lenses. Below: what the glasses are, what the evidence says about eyes and about sleep, and what to do instead.

What blue light glasses are

Blue light glasses have lenses with a coating or a tint that reflects or absorbs part of the blue end of visible light. The clear-looking kind filter a modest amount, often give white a faint yellow cast, and may show a blue or purple sheen when light catches them. Amber or orange tinted lenses filter much more, and are usually sold for evening wear and sleep rather than for eye strain.

They are easy to confuse with two other things that genuinely help some people:

• Computer glasses, sometimes called office or occupational lenses, are prescription glasses set for the distance of a screen, about an arm's length away. They make focusing at that distance easier, especially from your 40s on, when glasses set for reading a book are too close and glasses set for driving are too far.
• Anti-reflective coatings cut reflections on the lens itself, from ceiling lights and from windows behind you.

A pair of computer glasses can have a blue filter as well, which muddies things. When someone says their blue light glasses fixed their eyes, it is worth asking whether the prescription or the coating did the work.

Does blue light from screens damage your eyes?

Not as far as anyone has shown. The sun is a far bigger source of blue light than any screen, and the Academy's view that screen light does not harm the eye is the basis for its advice against special glasses for computer work.

Much of the worry traces back to laboratory work that exposed eye cells or animals to intense blue light, at levels a screen at arm's length does not come close to. Headlines about those studies traveled further than their details did.

Do blue light glasses help with eye strain?

The research says probably not. The Cochrane review pulled together the randomized trials that compared blue light filtering lenses with ordinary clear ones, and found little or no difference in eye strain from computer use in the short term. The trials were mostly small and short, so it is not the last word, but taken together they gave no sign of a large benefit.

That fits what is known about eye strain. Its usual causes are:

• Focusing up close for hours without a break.
• Blinking less often, and less fully, while you concentrate.
• Glare, and a screen much brighter or darker than the room around it.
• A screen too close, too high or too low.
• Glasses that are out of date, or none when you need them.

A filter does nothing for any of these. Some people still find their glasses more comfortable, and that is real to them: a slight tint can make a stark white screen feel softer, and an anti-reflective coating cuts glare. If you own a pair and like them, keep wearing them. Just don't let them stand in for the changes below, or for an eye exam.

Do blue light glasses help you sleep?

This is the stronger part of the case, and it is still weaker than the marketing. Light in the evening, especially light rich in blue, holds back melatonin, a hormone that rises before sleep, and can nudge your body clock later. That much is well established. Much of the clearest evidence, though, comes from bright light in lab conditions, which is a lot more light than a laptop at an evening brightness gives off.

Studies of amber glasses worn in the evening have given mixed results, and the Cochrane review found the evidence on sleep too uncertain to draw a conclusion either way. If evening screen light worries you, there are simpler steps with the same aim:

1. Turn on Night Shift in System Settings > Displays > Night Shift, with the Sunset to Sunrise schedule. Night Shift on Mac covers the setup and what it can and cannot do.
2. Turn the screen brightness down as the room gets darker. Less light overall matters more than its color.
3. Use warm, low lamps in the evening instead of bright overhead lights.
4. Stop screen work an hour or so before bed. For many people, what they are doing on the screen keeps them up more than the light coming off it.

What actually helps tired screen eyes

The changes that help are mostly about habits and the desk, and most take a minute to set up.

Three of these deserve a word more.

Breaks are the big one. The focusing muscles inside your eyes work steadily to keep near text sharp, and they only really relax when you look into the distance. The 20-20-20 rule is the simplest version: every 20 minutes, look 20 feet away for 20 seconds.

Brightness matters more than color. A screen glowing much brighter than the room is hard work for your eyes. On MacBooks and some displays, Automatically adjust brightness (in System Settings > Displays) keeps it in step with the room for you. True Tone, where your Mac has it, warms or cools the screen's white to suit the light around you, which many people find easier to look at.

Glasses matter most of all, if you need them. A small uncorrected prescription, or reading glasses set for a book rather than a screen, often explains why screen work feels like hard going. Tell your optometrist how long you spend at screens each day and how far away yours sits.

A nudge from the notch instead of a filter

Glasses work without you having to remember anything, which is a large part of their appeal. Breaks are the opposite. They only help if you take them, and the hours you most need one are the hours you are least likely to stop.

Notchpals hands that remembering to a character who lives in your Mac's notch. Blip, an alien who joins every crew at setup and is astonished by most things on Earth, looks after the Eyes side. A few times a day Blip drops down and asks for an eye break:

BlipYour eyes can focus near AND far? Amazing! Try far now. Twenty seconds!

Done means you looked; Later puts Blip off for a while. Blink breaks come the same way. Both draw on one daily allowance shared by the whole crew, set to Calm, Normal or Chatty, so you get a handful of nudges rather than one every 20 minutes. The only Eyes visit tied to the clock is a late evening request to dim the screen, which, going by the research above, is a better bet for your evenings than a tinted lens.

When to see an eye doctor

If your eyes keep aching, blurring or watering after a couple of weeks of breaks and a better placed screen, book an eye exam with an optometrist or ophthalmologist. See someone promptly for eye pain, a red eye, blurred or double vision that does not clear, or new sensitivity to light. Sudden flashes of light, a burst of new floaters, or a curtain or shadow over part of what you see need care the same day.