A cataract is a clouding of the natural lens inside your eye. This lens, located behind the iris, works just like the lens of a camera: by focusing light images on the retina; that sends images to the brain. As the human lens becomes clouded it keeps light and images from reaching the retina.
A cataract can be the reason sharp images become blurred, bright colors become dull, or seeing at night is more difficult. It may also be why the reading glasses or bifocals that used to help you read or do other simple tasks no longer seem to help. Vision with cataracts has been described as seeing life through old, cloudy film.
But a cataract is not a “film” over the eyes, and neither diet nor lasers will make it go away, nor can it be prevented. Sunlight, smoking, eye injury, certain diseases, or even some medications can cause the clouding. The best way to treat a cataract is with surgery that removes the old, clouded lens and replaces it with a new, artificial one to restore your vision, and, in many ways, significantly improves your quality of life.