As a child I recall mother saying, “Don’t sit too close to the TV”. “Do not read in bad lighting”. “Do not lay on your stomach in bed and read”. It will wreck your eye sight and cause you to need an eye glass prescription. Yet we know today mom meant well. While near point stress has been associated with myopia, science has not yet proven that reading in bad light is detrimental to eyesight and opinions do vary greatly.
What Studies on Humans Show
There is no scientific evidence that reading in poor light affects your eyes because there have been no studies on humans in this area to test the theory that poor lighting helps or harms the eyes.
In the late 1960s Eskimos who were introduced to modern civilization around World War II became more entrenched in modern culture, and myopia increased dramatically in groups of younger people. So much so that more than half of the children were myopic just 20 years after these Eskimos entered the civilized world.
Studies have been only done with monkeys and many of those show that eyestrain can lead to nearsightedness.
What the Evidence Shows
There is some support to the theory that reading in poor light may lead to myopia, or nearsightedness. The idea behind this is that in dim light you have to strain to see the words on the page, and this straining over time leads to myopia. Seeing part of the page or word, will cause your eyes to strain to see the rest. So when children who do a lot of reading and writing there is more eyestrain on their young eyes in this important developmental time of their life. There are articles that report evidence to support this risk in young children. So expect your eye doctor to express concern with prolonged visual use when using small digital devices and small computer games. In fact all excessive near visual tasks can raise the relative risk of making your child nearsighted.
To be complete this is a highly charged area of theory and opinion. Some claim there is a great deal of information that supports reading in poor light has no affect on the eye and there is no support that it causes permanent damage.
If you buy the eyestrain argument you could feed the kids supplements and chuck the books, TV, and needlepoint lessons, but the tradeoff might not be worth it. Having to wear eyeglasses is hardly a major handicap these days whereas being uneducated is. Till such time as the myopia-inducing component of civilization (if any) is isolated, you’re probably best off chalking up a little nearsightedness as a small price to pay for enlightenment. So what are you to do and what will most eye doctors recommend? Many eye doctors recommend visual breaks with any prolonged use of small computer games and reading. As a guide your eye doctor will most likely recommend keeping the room well illuminated and using a working distance of at least 20 inches away for a visual work period of 20 minutes and then taking a 20 minute break before repeating the cycle.
Most importantly have the eyes checked each year. A current prescription is as important as great visual working habits are in the reduction of visual stress coming from prolonged uninterrupted near point visual tasks.