Cataract /clouding/ is a manifestation of the ageing processes in the eye. Similar to grey hairs, ocular structures become less transparent as the years go by. About 50% of the population of up to 60 years of age has a cataract at some stage of development. This is clouding of the lens, which is part of the optical system of the eye. The cause for that process is unknown.
Ultraviolet and infrared rays, smoking, and some medicines are risk factors for the development of clouding. There are no proven prevention methods either.