The Basics of Nearsightedness

view of a city through eyeglass lenses

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Nearsightedness, or myopia, is an eye problem that causes objects at a distance to be blurry. A nearsighted person can clearly see objects that are close to them but has a hard time focusing on objects that are far away.

Signs and Symptoms

Someone with nearsightedness may squint noticeably when trying to view distant objects. They may also sit very close to the television or bring books very close to their eyes when reading. Sometimes nearsightedness causes people to be totally unaware of far away objects.


Nearsightedness occurs when the eyeball is slightly longer than normal, or when the cornea is steeper than average. These conditions cause light to focus in front of the retina instead of directly on its surface. In most cases, nearsightedness is inherited. However, there is some evidence that suggests that intense close-up activities, such as reading for prolonged periods of time at close range or playing video games for many hours, in early adulthood can induce nearsightedness. Although doctors often see this in clinical practice, research is still split on this as a cause of nearsightedness. In some countries, the population is so nearsighted, that it is considered a public health crisis or epidemic.


Nearsightedness is usually detected during childhood, between the ages of 10 and 20. It is often discovered when a child complains of not being able to the chalkboard. The condition often continues to get worse but stabilizes in the mid to late-twenties. Nearsightedness is diagnosed by a comprehensive eye examination completed by an optometrist or ophthalmologist. A refraction test will be performed during the examination confirming the diagnosis of myopia. In some cases, a cycloplegic refraction will be performed. A cycloplegic refraction may be important because younger people tend to measure slightly more nearsighted than they actually are. Some individuals over-focus or have accommodative spasm when tested.


Depending on the degree of nearsightedness, some people may only need glasses for driving or watching a movie. Others with a high degree of nearsightedness may only have clear vision a few inches from their nose. Nearsightedness can be treated with glasses, contact lenses or with laser procedures, such as LASIK. In some cases, myopia may also be treated with a corneal-reshaping procedure, although results are usually temporary in nature.

Cause for Concern

Nearsightedness may simply reduce your quality of life or cause eyestrain. In some cases, it may raise safety issues in the workplace and also increase your risk of certain eye diseases, such as glaucoma or retinal detachment. The more nearsighted an individual is, the higher the risk of having a retinal tear or detachment. 

A Word From Verywell

Because nearsightedness or myopia is on the rise in the United States and many other countries, parents are often interested in ways to reduce their children's risk of developing nearsightedness or become more nearsighted. Recent research by Justin C. Shermin in 2011 suggests that for each additional hour children spend outdoors per week, their risk of developing nearsightedness drops by two percent. Furthermore, a nearsighted child in one of the studies spent an average of almost 4 hours fewer hours per week outdoors than normal children or farsighted children. Another interesting relationship was examined as well. The study attempted to find out if children who spent more time outdoors also spent less time playing computer games, intense near reading or study. However, no relationship was found.

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