A cataract is a clouding of your natural lens, located behind your  pupil. The lens contains protein that degenerates with age. When you are  about 45 years-old, this change in the lens protein makes the natural  lens firmer and that’s why reading glasses are needed at that time.  Later, the lens protein begins to change color which makes the lens  cloudy. The result is a cataract and blurred vision.
