What Causes Cataracts?

Cataracts are the leading cause of treatable blindness in all parts of the world. By the age of 80, more than half of all Americans will have a cataract or will have undergone cataract surgery. A cataract impairs vision when the lens of the eye becomes cloudy, blocking the normal passage of light to the retina. A cataract can develop in one or both eyes, but can't spread from one eye to the other. Learn about the causes, symptoms, diagnosis and treatment of cataracts.

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Causes of Cataracts:

Most cataracts develop as part of the normal aging process. As we age, the normally clear lens of the eye slowly becomes cloudy. Over time, this clouding can cover the entire lens, significantly impairing vision. With advanced cataracts, it can become difficult to read or enjoy normal activities.

Symptoms of Cataracts:

When a cataract first begins to develop, you may not notice any changes in your vision. As the cataract grows, however, your vision may become blurred, cloudy, or foggy. The symptoms you experience depend on the type and progression of the cataract you have.

Types of Cataracts:

All cataracts involve a changing of the eye's lens, but there are several types of cataracts. Cataracts usually develop as a result of aging, but sometimes appear early in life. Different portions of the lens may be affected more than others. Eye doctors classify cataracts according to their location and origin.

Diagnosis of Cataracts:

An ophthalmologist or optometrist can diagnose the presence of a cataract by performing a comprehensive eye exam. In order to make a cataract diagnosis, your eye doctor will ask you certain questions and will perform certain tests. The diagnosis of a cataract is the first step toward clear and healthy vision.

Treatment of Cataracts:

Early cataract symptoms may be decreased by wearing stronger eyeglasses or contact lenses, using brighter lights, wearing anti-glare sunglasses, or using magnifying lenses. In advanced cases of cataract, surgery to remove the cloudy lens is the most effective treatment.

Preventing Cataracts:

Certain precautionary measures can be taken during your lifetime to decrease your risk of developing cataracts. Protecting your eyes from UV light and eating foods high in antioxidants are things you can do to help prevent or delay cataracts.

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Article Sources
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  2. National Eye Institute. Cataracts. Updated August 3, 2019.

  3. American Optometric Association. Nutrition and cataracts.