What are Cataracts?

The lens is a clear part of the eye. It sits behind the iris, which is the colored part of your eye. Normally, light passes right through the lens. A cataract forms when the lens becomes cloudy and blocks light.

Cataracts usually develop slowly with age. They can make your vision blurry or dull. It may feel like you are looking through a foggy window. These problems are often worse at night.

Brighter lighting and updated glasses can help when cataracts are small. If cataracts grow large enough to get in the way of daily life, surgery may be needed.

Last Reviewed and Updated: October 2026
By: AGS/HiAF Public Education Committee, HealthinAging.org Content Reviewers