Cataracts – Cataracts are a leading cause of vision issues for people over 40 and are one of the main causes of blindness. A cataract is a clouding of the eye, specifically in the eye’s lens behind the pupil, caused by proteins clumping together. There are different kinds of cataracts, and they can have different causes. Aging or other medical conditions can contribute to the development of cataracts in your eyes.