Cataract and latitude

Abstract

For many years, it has been suggested that exposure to sunlight, particularly its ultraviolet component, may be associated with an increased risk of senile cataract. This paper adresses 1) the physical and geographic variables that affect the entry of ultraviolet light in the eye; 2) the epidemiologic evidence that associates cataract with ultraviolet light exposure; and 3) the effectiveness of personal barrier protection (i.e. sunglasses and hats) in reducing ocular exposure to ultraviolet light. The epidemiologic evidence is drawn from studies in Australia, China, Tibet, and the United States. The U.S evidence consists of data from the Maryland Watermen study and analyses of cataract surge..