A cataract is a clouding of the eye's lens. It makes it hard for you to see. A cataract won't spread from one eye to the other, but many people get them in both eyes.

Normal Anatomy of the Eye
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As the cataract grows and gets cloudier, it may become harder to read and do other tasks. Many people are not aware that their eyesight is blurry because cataracts grow slowly over time.

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The cause of this clouding is not known. Many things can lead to cataracts forming, such as:

  • Aging
  • Smoking
  • Drinking too much alcohol
  • Health problems, such as diabetes
  • Some infections
  • Eye disease, or injury or burns of the eye
  • Exposure to radiation, toxins, or some medicines
  • Taking steroid medicines for a long time
  • Too much time spent in the sun
  • Problems found at birth
What are the risk factors for cataracts?What are the symptoms of cataracts?How are cataracts diagnosed?What are the treatments for cataracts?Are there screening tests for cataracts?How can I reduce my risk of developing cataracts?What questions should I ask my healthcare provider?What is it like to live with cataracts?Where can I get more information about cataracts?

Revision Information

  • Reviewer: EBSCO Medical Review Board James P. Cornell, MD
  • Review Date: 12/2018 -
  • Update Date: 02/14/2019 -