Refractive Errors

Is Myopia a Disease?


Myopia is not a disease. It does not affect the health of your eyes.

In medical terms, myopia (commonly called nearsightedness) is a refractive error. This means the eye does not bend (refract) light properly for good vision.

In a nearsighted eye, light is focused too quickly — in front of the retina instead of directly on the retinal surface. As a result, distant objects appear blurred while close objects are in focus.

Myopia is common in the United States, affecting an estimated 40 percent of the population, according to recent research. And if current trends continue, half the world’s population will be nearsighted by the year 2050.

Myopia promo 7: More time outdoors might lower your child's risk of myopia.

Myopia typically starts to develop during childhood and can progress gradually or rapidly. The most common symptoms of myopia are squinting, eye strain, headaches and fatigue.

Genetics plays a role in myopia. It's not unusual for generation after generation of the same family to be nearsighted. But environmental factors also have an influence. In other words, a child who spends more hours indoors reading and playing computer games might have a greater risk of becoming nearsighted than his or her brother who spends more time outdoors playing sports.

It appears that any sustained near activities — such as reading and leisure time spent in front of screen media like computers and handheld video games — put stress on the eyes that contributes to the risk of becoming nearsighted. One theory is that myopia actually is the eye’s way of adapting to this type of near focusing stress. [Read more about screen time and kids.]

The younger children are when they first become nearsighted, the higher their risk is of becoming very myopic by the time they are adults. This is a serious concern because high myopia is associated with vision-threatening eye diseases, including glaucomacataracts and retinal detachment.

Fortunately, myopia is easily discovered during routine eye exams. Blurred vision caused by nearsightedness typically is easily corrected with eyeglasses or contact lenses. There also are treatment options with special glasses and contacts that are designed to slow the progression of myopia in kids (myopia control).

Myopia typically stops getting worse in early adulthood. Once nearsightedness has stabilized, LASIKPRK and other refractive surgery procedures also are good treatment options.

Page updated October 2018