There have been 3 other prospective studies that have examined the relationship between dietary intake of lutein and risk of cataract. In the Nurses' Health Study of 77 466 female nurses, women in the top 10% of lutein/zeaxanthin intake, compared with those in the bottom quintile, had a 22% lower risk of cataract extraction (RR, 0.78; 95% CI, 0.63-0.95; test for trend, P = .04) during 12 years of follow-up.28 In another study32 from that cohort, based on a small subsample of 408 participants, there was no association between intake of lutein/zeaxanthin and 5-year change in nuclear density as measured by analysis of digital images. In a second study,27 data from the Health Professionals Study of 36 644 male health professionals showed that men in the highest quintile of lutein/zeaxanthin intake, compared with those in the lowest quintile, had a 19% lower risk of cataract extraction (RR, 0.81; 95% CI, 0.65-1.01; test for trend, P = .03) during 8 years of follow-up. A third study,29 based on data from 1354 men and women participating in a nutrition substudy of the Beaver Dam Eye Study, showed that those in the highest quintile of intake of lutein/zeaxanthin in the distant past (10 years before baseline), compared with those in the lowest quintile, had a 50% decreased risk of incident nuclear opacity (odds ratio, 0.5; 95% CI, 0.3-0.8; test for trend, P = .002) at 5 years of follow-up. The present data from a large cohort of female health professionals indicate an approximately 20% decreased risk of cataract for those with high dietary intake of lutein/zeaxanthin and, thus, seem most consistent with the findings for cataract extraction reported in the Nurses' Health Study and the Health Professionals Study.27- 28 Of note, lutein/zeaxanthin intake in the reference group in the WHS and the 2 other cohorts of health professionals27- 28 seem markedly higher than the reference intake for lutein/zeaxanthin in the population-based sample from Beaver Dam, Wisconsin,29 which may at least partially explain the smaller risk reductions observed in the former.