Selenium concentrations in serum, lens and aqueous humour of patients with senile cataract. Cataractogenesis may be caused either by the excess or deficiency of this trace element. More recently, its potential of becoming a possible environmental pollutant has been emphasized. It is anticipated that decreased Se in aqueous humour and sera of patients with senile cataract may reflect defective antioxidative defense systems which may lead to the formation of cataract. Associations between nutrition and cataract.
Cataracts are even more prevalent in some other populations.
It is estimated that the need for cataract extractions would be diminished by half if onset of cataract could be delayed by only ten years. Hypotheses regarding the etiology of cataract include oxidative perturbations of protein metabolism, diverse pathologic conditions, and perhaps glycation of lens proteins. Biochemical evidence suggests that each of these compounds can delay photooxidative damage to lens proteins. Roles in lens metabolism for selenium and tryptophan have been suggested. Elucidation of mechanisms by which caloric restriction delays cataract development is a promising area of current research.