Nearsightedness, medically known as myopia, is the most common cause of poor eyesight, especially in younger adults. It refers to being able to see well at close range, but not at a distance.

Myopia (nearsightedness) is a common vision problem experienced by almost one-third of the people across the U.S. population. While nearsighted people can see very well up-close and can perform tasks such as reading without difficulty, their distance vision is unfocused. Because of myopia, driving, playing sports and participating in other activities requiring distance vision often becomes difficult. Some of the most common signs of myopia are:

• Blurred distance vision
• Eyestrain
• Headaches
• Frequent squinting when viewing distant objects
• Unusual fatigue after playing sports or driving

Nearsightedness is said to be caused by an elongation of the eyeball. This means that the oblong (as opposed to normal spherical) shape of the myopic eye causes the cornea and lens to focus at a point in front of the retina. A more precise explanation is that there is an inadequate correlation between the focusing power of the cornea and lens and the length of the eye.

Singapore is the first country in the world to publicly state that nearsightedness is caused by prolonged close work. Myopia is fairly common worldwide. Approximately 25% of the U.S. population is myopic to some degree, affecting men and women equally. There is greater prevalence of this disorder among children from higher socio-economic groups, although the reasons for this remain unclear. Incidence is much higher in certain Asian countries. Taiwan experiences the worlds highest rate. In some nations, such as Singapore, the incidence has rapidly increased over the past decade.

There are many types of myopia. Some common types include:

• Physiologic
• Pathologic
• Acquired

Studies have shown that genes play a major part in nearsightedness forming, and plenty of studies already show that myopia is passed from parents to children. For example, nearsightedness is more common in children of myopic parents than children of non-myopic parents. So if scientists can identify nearsightedness genes, treatments can specifically be created for children who are genetically more likely to develop myopia. Perhaps drug or gene therapies can even help make the condition less severe.

The more education you have, the more myopic you may be. At first glance, this fact seems like fiction. However, the rationale is that more education means you read more, which puts stress on the eye. It is this stress that can exacerbate existing vision problems or create them.

Here are some most useful tips for preventing nearsightedness and its progression.

• Eye-exercises and biofeedback. Practitioners and advocates of alternative therapies often recommend eye exercises and relaxation techniques such as the Bates method. However, the efficacy of these practices is disputed by scientists and eye care practitioners.
• Daylight. Daylight may prevent myopia. Australian researchers had concluded that exposure to daylight appeared to play a critical role in restricting the growth of the eyeball, which is responsible for myopia or short-sightedness.
• Myopia control. Various methods have been employed in an attempt to decrease the progression of myopia. The use of reading glasses when doing close work may provide success by reducing or eliminating the need to accommodate. In some study, bifocal and progressive lenses have not shown significant differences in altering the progression of myopia.
• Convex lenses. Some clinicians and researchers recommend plus power (convex) lenses in the form of reading glasses when engaged in close work or reading instead of using single focal concave lens glasses commonly prescribed. The reasoning behind convex lense’s possible effectiveness in preventing myopia is simple to understand: Convex lenses’s refractive property of converging light are used in reading glasses to help reduce the accommodation needed when reading and doing close work.
• Pirenzepine eyedrops. Pirenzepine eyedrops had a limited effect on retarding myopic progression in a recent, placebo-control, double-blinded prospective controlled study.

There is no universally accepted method of preventing myopia. Commonly attempted preventative methods include wearing reading glasses, eye drops and participating in more outdoor activities are described below.