Does reading in dim light damage your eyes?

It’s a popular myth and most likely one that was drilled into you by parents (and one that you probably subsequently drilled into children and grandchildren): reading in low lighting will damage your eyes. But for those who enjoy a book in the soft glow of a bedside lamp or kids who like to hide under the covers with a torch, there’s no need to worry – reading in the dark actually doesn’t damage your eyes at all.

Why do my eyes feel tired then?

There is no scientific evidence to suggest that reading in poor lighting conditions damages eyes but it does strain your eyes. Dim light might make it difficult for the eyes to focus, which can make reading more strenuous and cause short-term eye fatigue. While uncomfortable, there isn’t any long-term harm or damage to the structure of function of eyes.

So there’s really no risk?

Well, not for reading in dim light but too much reading in any light can be damaging. There’s evidence that people who read a lot or work in other types of “close eye” work such as using a computer or sewing have higher rates of myopia or short-sightedness. Nobody knows exactly why but a possibility is that the constant focusing on close objects – which involves the contraction of muscles controlling the shape of the eye's lens – may stretch the eyeball and become more short-sighted. So reading a lot, whether in the dark or bright light, could encourage short-sightedness.

Why the size of your glasses matters

So what should I do?

There’s no need to be concerned you’re doing permanent damage to your eyes if the day turns to dusk and you’re still engrossed in a book but you’ll probably be more comfortable turning on the light. It’s also a good idea to give your eyes a break now and then when reading for long periods of time. Close your eyes or try some eye yoga exercises in your break and your eyes should be feeling refreshed and ready to read again.