Coffee consumption may be associated with a lower risk of malignant melanoma, according to a recent study published in the Journal of the National Cancer Institute.
Cutaneous melanoma is the leading cause of skin cancer in the United States, with an estimated 770,000 reported new cases and 9,500 deaths in 2013. Exposure to ultraviolet radiation (UVR), especially UVB, is the only reliable risk factor for melanoma, but evidence has shown a possible protective role of coffee consumption in UVB-induced carcinogenesis.
Coffee constituents have been found to suppress UVB-induced skin carcinogenesis, induce cell apoptosis, protect against oxidative stress and DNA damage, reduce inflammation in epidermal cells, and inhibit changes in DNA methylation.
The existent epidemiological studies of coffee consumption and melanoma have shown inconsistent results when it comes to a direct association between coffee intake and the risk of malignant melanoma.
A team of researchers led by Erikka Loftfield, MPH from the Division of Cancer Epidemiology and Genetics, National Cancer Institute in Rockville, and colleagues assessed coffee intake at baseline with a food frequency questionnaire in the National Institutes of Health–AARP prospective cohort study, on a total of 447,357 non-Hispanic whites.
After a median follow-up period of 10.5 years, a total of 2,904 cases of malignant melanoma were identified. Additionally, researchers examined coffee intake and subsequent melanoma risk with non–coffee drinkers as the reference group using Cox-proportional hazard models.
Results revealed that those with a higher coffee intake (4 cups per day or more) had a 20% lower risk of malignant melanoma, with a trend towards higher consumption correlating with a higher protection effect. This association was found for caffeinated but not for decaffeinated coffee, and only for malignant melanoma but not melanoma in-situ, suggesting that there may be different skin cancer aetiologies.
In their article “Coffee Drinking and Cutaneous Melanoma Risk in the NIH-AARP Diet and Health Study”, the research team concluded that in this large U.S. cohort study, higher coffee intake is significantly associated with a moderate decrease in the risk of malignant melanoma. However, further studies investigating coffee intake and its components, especially caffeine, with melanoma are necessary.