The overall goal of the proposed research is to determine the relationship of diet and vitamin or mineral supplement use on the prevalence and progression of age-related eye diseases of cataract and macular degeneration. These investigations are aimed at providing insight into the etiology of these eye diseases. It is anticipated that such information will ultimately lead to preventive measures to delay the onset of these common causes of blindness and disability in older adults. Data on diet and use of vitamin and mineral supplements have already been collected in 91% of a 50% random sample of all people residing In Beaver Dam, Wisconsin between the ages of 43 and 85 who have participated in the Beaver Dam Eye Study (BDES). The first objective of this proposal Is to utilize this data to determine whether the intake of specific foods or food groups is associated with the prevalence of age-related cataract and maculopathy. These analyses, In conjunction with the analyses of nutrients alone, help identify the nutrients or foods which are more likely to directly affect the occurrence of these diseases. In addition, the proposed research also expands the depth of these investigations into the influence of several nutrients, recently implicated to play roles In the development of these eye diseases. We plan to conduct nested case-control studies of this population to quantitate the association between the prevalence of age-related cataract and age-related maculopathy (ARM) and blood levels of biochemical markers of antioxidant defense, singly and combined, in an antioxidant index. The relationship between serum levels of 25-hydroxyvitamin D and cortical cataract prevalence will also be determined in a case-control study in this population. The second phase of the proposed research will be conducted in conjunction with a planned five-year follow-up eye examination in the BDES. New data on diet and use of vitamin and mineral supplements will be collected from all surviving members of the original diet study cohort. These data will be used along with past dietary data to quantitate the associations between the intake of specific nutrients and foods at three points in time, on the progression of age-related cataract, and ARM. Individuals with photographic evidence of progression of cataract and ARM at five-year examinations and controls (persons with no progression of these diseases) will be included in case-control studies to quantitate the association between progression of these diseases and baseline biochemical markers of antioxidant defense. Blood specimens collected at the time of the five-year follow-up examinations will be used to study the relationship between zinc status and severity of ARM in a nested case-control design.