Cataracts may result from many conditions including congenital defect, chronic eye disease, system-wide diseases (diabetes), or eye trauma, but by far the most common cause of cataracts is simply age. Cataracts are the leading cause of vision loss among older Americans. By the time you are between 75 to 84 years of age, the probability of cataract development reaches nearly 90%.
In the initial stages of cataract development you may not notice any vision change because the cataract is small. Cataracts tend to grow slowly so vision deteriorates slowly. Some people with a cataract find that their close-up vision suddenly improves, but this temporary effect dissipates as the cataract grows. Common symptoms of a cataract are: