A cataract is a cloudy or opaque area in the normally clear lens of the eye. Depending upon its size and location, it can interfere with normal vision. Most cataracts develop in people over age 55, but they occasionally occur in infants and young children. Usually cataracts develop in both eyes, but one eye may have somewhat worse vision than the other. Early symptoms of cataracts include blurred vision, glare and difficulty reading. Cataracts generally progress very slowly, and surgery may not be needed for many years, if at all. In some cases, periodically changing your eyeglass or contact lens prescription may continue to provide you with good vision. There is no way to prevent cataract development. Currently, the only way to treat cataracts is to surgically remove the natural lens in the eye.