Types

What Are Cataracts?

Choose a preferred language

The lens in the eye focuses light so the eye sees images sharply. Aging is the most common cause of cataracts. With age, the lens slowly becomes cloudy. The cloudy lens is a cataract. A cataract scatters light and makes it hard for the eye to focus. Cataracts usually form in both eyes. But one lens may cloud faster than the other.

Three-quarter view of eye showing lens sharply focusing light. Three-quarter view of eye showing cataract scattering light.


The aging of your lens

Your lens may cloud so slowly that you don`t notice any vision changes at first. But as the cataract gets worse, the eye has a harder time focusing. In early stages, glasses may help you see better. As the lens gets more cloudy, your healthcare provider may advise surgery to restore your vision.

A clear lens allows your eye to bring objects sharply into focus.

A mild cataract may slightly blur your vision.

A dense cataract can severely blur your vision.

© 2000-2026 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.
schedule icon

Schedule an Appointment

Find the right provider and schedule anytime.

View Providers
Related Articles
Read article
Eye Care
Conjunctivitis, Allergic

Allergic conjunctivitis is caused by an allergen. Symptoms may include redness of the eye, swelling, fluid leakage, and itching or burning.

Read article
Eye Care
Uveitis

Uveitis is inflammation inside the eye. This can be caused by injury to the eye or disease somewhere else in the body. Symptoms include eye pain, redness, blurred vision, sensitivity to light, and floating spots in the vision.

Read article
Eye Care
Pterygium

A pterygium is a noncancerous growth that starts in the conjunctiva. It can cause eye irritation, itching, and redness. If the growth is large, it can cause vision problems.

Read article
Eye Care
Understanding Iritis

Iritis is the inflammation of parts of the eye. It causes pain, sensitivity to light, and other problems.