CATARACT AND UV-RADIATION

The idea that UV radiation causes cataract has superficial biological plausibility based upon studies of UV-B on lens components, whole lens es and experimental animals. However, epidemiological studies on man, particularly geographical studies, are highly confounded by socioecono mic factors and yield little information. Population-based exposure-ca taract studies are preferable since UV incidence versus UV exposure ca n be weighted with respect to risk and protective factors. However, th e cataractogenic potency of UV seems to be low and certainly lower tha n the cataractogenic potency of factors such as repeated diarrhoea so that it is doubtful whether a clear answer to the question 'Does UV ca use cataract' will ever be provided.