Nearsightedness is an eye condition in which you can see nearby objects clearly, but faraway objects appear fuzzy or blurry. It’s also called myopia.
Nearsightedness is extremely common but treatable. According to the American Optometric Association, almost 30 percent of Americans are nearsighted.
The most obvious symptom of nearsightedness is blurry vision when you look at faraway objects. Children may have trouble seeing the blackboard at school. Adults may not be able to see street signs clearly while driving.
Other signs of nearsightedness include:
- eyes that hurt or feel tired
The symptoms of nearsightedness usually go away after treatment with eyeglasses or contact lenses. Headaches and eye fatigue may linger for a week or two as you adjust to your new eyeglass or contact lens prescription.
According to the National Eye Institute, myopia is often diagnosed between the ages of 8 and 12. Your eyes are growing at this age, so the shape of your eyes can change. Adults usually remain nearsighted if they have the condition as a child. Adults can also become nearsighted due to certain health conditions, such as diabetes.
Visual stress is another risk factor for nearsightedness. This is eyestrain from doing detailed work, such as reading or using a computer.
Nearsightedness can also be an inherited condition. If one or both of your parents are nearsighted, you’re more likely to be as well.
Nearsightedness is caused by a refractive error. A refractive error occurs when your eye doesn’t focus light correctly. If you’re nearsighted, your eye focuses light in front of your retina instead of onto it. This results in blurred vision.
The retina is the surface at the back of your eye that collects light. It changes the light into electrical impulses that your brain reads as images.
A myopic, or nearsighted, eye focuses incorrectly because its shape is slightly abnormal. A nearsighted eyeball is usually a little too long, and sometimes its cornea is too rounded. The cornea is the clear covering on the front of your eye.
Your eye doctor can diagnose nearsightedness by performing a complete eye exam.
Correction for nearsightedness may include:
- corrective lenses
- corneal refractive therapy
- refractive surgery
Eyeglasses and contact lenses are examples of corrective lenses. These devices compensate for the curvature of your cornea or the elongation of your eye by shifting the focus of light as it enters your eye.
Your prescription strength will depend on how far you can see clearly. You may need to wear corrective lenses all the time or just for certain activities, such as driving.
Contact lenses generally give you a wider field of corrected vision than glasses. They’re applied directly to the corneas of your eyes. Some patients can’t tolerate contact lenses because they irritate the surface of their eyes.
Refractive surgery is a permanent form of correction for nearsightedness. Also called laser eye surgery, the procedure reshapes your cornea to focus light onto your retina. Most people who have refractive eye surgery no longer need to wear contact lenses or eyeglasses.
Most nearsighted patients see marked improvement with treatment. Early treatment of myopia can prevent social and academic difficulties that can accompany poor eyesight.
You can’t prevent nearsightedness. However, according to the Mayo Clinic, some research suggests you may be able to slow its development.
To help protect your eyes:
- Get your vision checked regularly.
- Wear corrective lenses prescribed by your eye doctor.
- Wear sunglasses with ultraviolet (UV) radiation protection.
- Use protective eyewear when doing risky activities, such as using toxic chemicals.
- Take regular breaks from detailed work, such as looking at your computer screen.
- Manage chronic health conditions, such as high blood pressure and diabetes.
- Eat a diet rich in fruits, vegetables, and omega-3 fatty acids.
- Avoid smoking.
If you notice any changes in your vision, such as blurred vision or halos around lights, contact your eye doctor immediately. Taking good care of your eyes may help you see better for longer.
Written by: Erica Roth
Medically reviewed on Feb 26, 2016 by Hannah Nam, MD