Reading in dim light will ruin your eyesight.
Don’t Believe That!
This probably ranks in the top three things most likely to be heard from Mom, along with “don’t swim within an hour of eating” (not necessary) and “don’t run with scissors” (still good advice).
Generations of parents have passed along this warning. There is however, no evidence that reading in low illumination causes any damage to your eyes. It can, however, cause temporary eye strain and even blurred vision or headaches (which is probably the source of this belief).
According to experts, including the American Academy of Ophthalmology, your eye muscles must work a bit harder to focus in lower light conditions. Eventually, the muscles become strained from the extra work and your eyes may even feel sore. This is similar to being sore after a workout – the discomfort goes away eventually with no permanent damage done. Reading in general also results in less blinking, which can lead to dry eyes.
Bonus Fact: The muscles that control your eyes are the most active – and fastest – muscles in your entire body.