A cohort study of vitamin D intake and melanoma risk.

Data suggest that vitamin D intake may have chemopreventive efficacy against melanoma, but there have been no published epidemiologic studies examining the association between vitamin D intake and melanoma risk in a large prospective cohort. We examined whether dietary and supplemental vitamin D intake was associated with melanoma risk among 68,611 men and women who were participants of the Vitamins and Lifestyle cohort study. Participants reported dietary vitamin D intake over the past year and 10-year use of multivitamin and individual vitamin D supplements on a baseline questionnaire. After follow-up through 2006, 455 incident melanomas were identified through linkage to the Surveillance, Epidemiology, and End Results cancer registry. Cox proportional hazards regression models were used to estimate relative risks (RRs) and 95% confidence intervals (CIs) for vitamin D intake after adjustment for melanoma risk factors. Compared with the lowest quartile, we did not detect a risk reduction of melanoma in the highest quartiles of dietary vitamin D intake (RR=1.31, CI=0.94-1.82), 10-year average supplemental vitamin D intake (RR=1.13, CI=0.89-1.43), or combined dietary and supplemental intake (1.05, CI=0.79-1.40). In this large prospective cohort, we did not find an association between vitamin D intake and melanoma risk.