Can reading in the dark damage your vision?

If you’re an avid reader, you’ve probably been told to turn a light on while reading so you don’t harm your eyes. According to most ophthalmologists, however, while reading in the dark temporarily strains your eyes, it won’t permanently damage your vision. In other words, it’s safer than most people think to read under the covers with a flashlight late into the night.

The reason most experts believe that reading in the dark won’t cause lasting damage is because your eyes are naturally designed to adjust to different levels of light.

In the dark, your pupils dilate to take more light into your retinas through the lens. Photoreceptors in your retina then convey information about what you can see to your brain. That’s why when you enter a dark room or turn off the lights, you’ll notice that you’re gradually able to see more as your eyes adjust.

Your eyes also regulate when reading in dim light. The extra effort can place strain on the various components of your eyes. This can potentially cause you to experience eyestrain, headaches, blurred vision and back and neck strain.

While these symptoms are unpleasant, they won’t cause lasting damage and should go away on their own. If they don’t, you may have an underlying condition and should see your optometrist right away.