The lens of the eye, located just behind the pupil and iris, is composed of protein and water. The protein is organized in a specific structure to ensure that it is transparent. The lens of the eye works similarly to a camera lens in that it focuses an image on the retina. Cataracts are characterized by a clouding of the lens. The clouding is caused by clumping of the specially structured protein. The clumps block light and interfere with vision. Over time the clumps grow larger and affect more of the lens, thereby interfering with a greater field of vision.

More than half of Americans 65 years and older have cataracts. Cataracts are indeed most commonly related to aging. Other types of cataracts include congenital cataracts, which are present at birth or develop in childhood, secondary cataracts develop due to other health problems such as diabetes, while traumatic cataract occurs after an eye injury.

Symptoms of cataracts include:

  • cloudy or blurry vision
  • headlights that seem too bright or glary
  • halo around lights
  • faded color perception
  • poor night vision
  • double or multiple vision

It is not yet clear what causes cataracts, but some environmental factors and diseases are known to contribute to the condition. Among these are smoking, excessive exposure to sunlight, and diabetes. Steroid use has also been shown to increase the incidence of cataracts.

Taking preventive measures

While it seems almost inevitable that a cataract will develop as a result of normal aging, some preventive measures can be taken to delay the onset or slow the progression of the disease.

Some preventive measures include:

  • wearing sunglasses, wide brimmed hats
  • avoiding cigarette smoke
  • maintaining a diet high in antioxidants (beta carotene, selenium, vitamins C and E)


Treatment of cataracts is dependent upon the stage of the condition. During the early stages a different eyeglasses prescription, magnifying lenses, or stronger lighting may enhance vision. Surgery is usually indicated when vision loss interferes with everyday activities such as driving, reading or watching television. The surgical procedure involves removal of the cloudy lens and replacing it with an intraocular lens (a clear, artificial lens). This is one of the most common operations performed in the United States, with over 1.5 million done each year. 90% of patients have better vision afterward.

Your eyecare professional can determine if you have a cataract. He or she can also counsel you on the steps you can take to reduce your chances