The word cataracts is used to describe the condition where the lens of the eye acquires a cloud-like appearance which in turn leads to poor vision, it is a condition which is mostly common among the elderly aged above the age of 65.
They occur when there is a high level of protein in the lens. This is a result of build up and it causes the lens to be cloudy. As a result, it is difficult for light to pass through it clearly which also means that the individuals is not able to see clearly. This is because the lens is responsible for effectively bending rays of light entering the eye so as to focus objects sharply on the retina lining which is situated at the back of the eye. The lens is located behind the iris which is the part that gives eyes their color.
Cataracts are caused by the changing of the structure of lens proteins. These are found within the lens and are tasked with causing it to continue being clear. After many years have passed by however, and with the passage of time, their structure becomes altered and as a consequence, the development of cataracts is a process which takes place over a prolonged period of time.
Only in rare occasions is this not the case where they are then caused by too much exposure to ultra-violet light, use of steroids smoking and even diabetes. An examination of the eyes is a good test to diagnose correctly and know for sure. Symptoms however include; seeing double, change in the perception of color, foggy vision, problems with glare and so on.