US researchers looked at the possible association between dietary and supplemental vitamin A and carotenoid intake and melanoma, using data from the VITamins And Lifestyle (VITAL) cohort study.
The analysis was carried out in 69,635 men and women with an average follow-up of 5.84 years and 566 incident melanomas were identified, of which 257 were in situ and 309 invasive tumours.
Among retinol supplement users, 16 invasive melanomas were detected. The researchers also found the risk reduction to be stronger in sun-exposed areas, such as the limbs, head and neck, than in the trunk.
Only study participants who were currently taking the retinol supplement had a statistically significant risk reduction. There was no association of retinol intake from food sources or the combination of supplements and food intake and melanoma risk. The authors admit to study limitations, but suggest that vitamin A supplementation might be a potential chemopreventive agent for melanoma.
Asgari MM, Brasky TM, White E. J Invest Derm 2012; 132: 1573-82