With rates of “myopia” (nearsightedness) increasing worldwide, many are labeling it a “myopia epidemic.” When trying to attach a specific cause to this pervasive problem, cell-phone use comes to mind. It may seem to make sense that spending more time squinting into the screen of a handheld digital device may make users more prone to nearsightedness, but there is another, more likely cause.Research indicates that, as children spend less time outdoors than peering into computer screens, they are depriving themselves of the sunlight needed to preserve good eyesight. Scientists speculate that natural light stimulates the normal release of dopamine (a major neurotransmitter in the retina) that guards against nearsightedness. If so, more time spent outdoors may help avert myopia.
P.S. In the United States and Europe, about one-half of children and young adults are thought to be nearsighted, which is double the prevalence of myopia a half century ago.