Antioxidants Do Not Increase Melanoma Risk
Antioxidants such as vitamins C and E, beta-carotene, and the minerals selenium and zinc do not increase the risk of melanoma, according to a new study released in the August issue of Archives of Dermatology. This newest study refutes the findings of the SUVIMAX (Supplementation in Vitamins and Mineral Antioxidants) study, which stated that antioxidant supplementation increased the risk of melanoma by four-fold in women who took the nutrients.
Melanoma is the most serious form of skin cancer: although it accounts for less than 5 percent of skin cancers, it is responsible for a large majority of skin cancer deaths. The American Cancer Society estimates that about 68,720 new melanomas will be diagnosed in the United States in 2009, and about 8,650 people will die of the disease in the same year.
The report that antioxidants, which are found naturally mostly in fruits and vegetables, could increase the risk of melanoma was of great concern given that between 48 and 55 percent of adults in the United States take vitamin or mineral supplements. If such research results were true, changes would need to be made in how people took supplements.
In the newest study, the researchers evaluated the data that had been collected over ten years on 69,671 men and women who had participated in the Vitamins and Lifestyle (VITAL) study. VITAL was started in 2000 and was designed to assess the relationship between the use of supplements and the risk for cancer. The investigators did not find any association between the use of supplements, including beta-carotene, zinc, selenium, and vitamins C and E, and the risk for melanoma.
The results of the SUVIMAX study were questioned after they were published in 2007. In an editorial in the American Society for Nutrition, clinicians argued that the some of the cases of melanoma seen in the study were unlikely to have been caused by the supplements because they occurred too early in the intervention period, and the melanomas probably had been present in preclinical form given that the disease has a long latent period. Another argument is that the study’s declaration of a fourfold increase in the risk of melanoma was based on only 16 cases in women.
The current study’s authors point out that in addition to their findings, the Nurses’ Health Study also found no association between the intake of vitamins A, C, and E and the risk of melanoma in 162,000 women during more than 1.6 million person-years of follow-up.
One of the main contributors to development of melanoma is exposure to the sun. Some studies have shown that application of topical antioxidants such as vitamins C and E, green tea extracts, and even pomegranate can protect the skin against damage from the sun.
Afaq F et al. Exp Dermatol 2009 Jun; 18(6): 553-61.
American Cancer Society
Asgari MM et al. Arch Dermatol 2009; 145(8): 879-82.
Green AC et al. J Nutr 2008; 138(5): 978-79.
HealthDay News, 8/17/09