Home/Resources/Blue light glasses

Eyewear

Do blue light glasses actually work?

From the doctors at Webb Eyecare

Probably not for the reason they are sold to you. The evidence that blue light from screens damages your eyes is weak, and the research on blue-filtering lenses relieving eye strain has been mixed at best. That is an unsatisfying answer, so here is the more useful one.

What screens are actually doing to your eyes

The discomfort is real. The cause is mostly mechanical rather than spectral.

• You blink far less when concentrating on a screen, sometimes less than half as often. That dries the eye surface out.
• You hold focus at one distance for hours, which is sustained muscular effort.
• Both eyes converge inward the whole time to keep one image, which is more effort again.
• Glare and poor lighting make all of the above harder.

None of those is a blue light problem, which is why a blue light filter often does not fix them.

What about sleep?

This is the one area where blue light genuinely has an effect. Light in the evening, particularly at the blue end, can influence the body clock and make falling asleep harder. If your complaint is sleep rather than sore eyes, reducing evening screen brightness or use is more reliable than a lens.

What actually helps tired eyes

• The 20-20-20 habit: every 20 minutes, look at something about 20 feet away for around 20 seconds. It resets the focusing effort.
• Blink deliberately, and treat dryness if it is there rather than pushing through it.
• Get the prescription right: a small uncorrected error is exhausting over eight hours even if you see fine.
• Set the screen up properly: slightly below eye level, an arm's length away, and not brighter than the room.
• Consider a lens designed for screen distance, which is a different thing from a blue filter.

So should you buy them?

If you already have a pair and you like them, there is no reason to stop wearing them. They are not harmful. What we will not do is sell them to you as protection your eyes need, because that is not what the evidence supports.

If screens are making your eyes ache, the more productive step is an exam. Tired eyes at the end of a workday are very often an uncorrected prescription, dry eye, or a focusing problem, and all three are treatable.

More on the mechanics: why your eyes hurt after a day of screens.