Association of vitamin A and carotenoid intake with melanoma risk in a large prospective cohort.

Laboratory data suggest that intake of vitamin A and carotenoids may have chemopreventive benefits against melanoma, but epidemiological studies examining the association have yielded conflicting results. We examined whether dietary and supplemental vitamin A and carotenoid intake was associated with melanoma risk among 69,635 men and women who were participants of the VITamins And Lifestyle (VITAL) cohort study in western Washington. After an average of 5.84 years of follow-up, 566 incident melanomas were identified. Cox proportional hazards regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of melanoma associated with dietary, supplemental, and total vitamin A and carotenoid intake after adjusting for melanoma risk factors. Baseline use of individual retinol supplements was associated with a significant reduction in melanoma risk (HR: 0.60; 95% CI: 0.41-0.89). High-dose (>1,200 μg per day) supplemental retinol was also associated with reduced melanoma risk (HR: 0.74; 95% CI: 0.55-1.00), as compared with non-users. The reduction in melanoma risk was stronger in sun-exposed anatomic sites. There was no association of melanoma risk with dietary or total intake of vitamin A or carotenoids. Retinol supplementation may have a preventative role in melanoma among women.