Objective: An association between caffeine intake and the risk of skin cancer has been suggested in animal studies, but has not been well established in epidemiologic studies. The objective of this study is to prospectively examine the association between coffee consumption and the risk of skin cancer.

Materials and Methods: Using data from two large cohorts in the U.S., the Nurses' Health Study (NHS) and the Health Professionals Follow-up Study (HPFS), we prospectively examined the risks of basal cell carcinoma (BCC), squamous cell carcinoma (SCC), and melanoma according to coffee consumption. In the NHS, 72,921 participants were followed up from June 1984 to June 2008. In the HPFS, 39,976 participants were followed up from June 1986 to June 2008. We documented 25,480 incident skin cancer cases in the two cohorts, which comprised 22,786 BCC, 1,953 SCC, and 741 melanoma cases. Cox proportional hazard models were used to calculate relative risks (RRs) and 95% confidence intervals (CIs), adjusted for confounding variables and skin cancer risk factors.

Results: A significantly inverse association was found between coffee consumption and BCC risk. The dose-response relationship was significant (P trend < 0.0001 in women, and P trend = 0.005 in men). Compared with people who consumed coffee < 1 cup/month, those who consumed > 3 cups/day had a RR of 0.80 (95% CI: 0.75, 0.85) in women, and 0.91 (95% CI: 0.81, 1.02) in men. The amount of caffeine consumption was also inversely associated with BCC risk. The highest quintile had the lowest risk (in women RR = 0.82; 95% CI: 0.78, 0.87, and in men RR = 0.87; 95% CI: 0.81, 0.94, both P trend < 0.0001). Decaffeinated coffee consumption was not associated with a decreased risk of BCC. Neither SCC nor melanoma was found to be inversely associated with coffee consumption.

Conclusion: Coffee consumption is inversely associated with BCC risk in women and men, likely through the effect of caffeine. Further studies are warranted to investigate the underlying mechanism.

Citation Information: Cancer Prev Res 2011;4(10 Suppl):B106.