Coffee may protect against a slow growing skin cancer: Study

By Dr. Ananya Mandal, MDOct 25 2011

A new study shows that drinking coffee was associated with decreased risk of a common and slow-growing form of skin cancer called basal cell carcinoma.

The researchers based at Brigham and Women's Hospital and Harvard Medical School in Boston, presented their study at the American Association for Cancer Research International Conference on Frontiers in Cancer Prevention Research.

The team looked at data from the Nurses' Health Study, which followed 72,921 people between 1984 and 2008, and the Health Professionals Follow-Up Study, which followed 39,976 people between 1986 and 2008, they found 25,480 skin cancer cases. Basal cell carcinomas represented 22,786 of the cases, squamous cell carcinomas 1,953 and melanomas 741.

They noted that women who drank more than three cups of coffee had a 20% reduction in risk for basal cell carcinoma.  Men who drank that much coffee had a 9% reduction in risk of the slow-growing cancer.  People who drank the most coffee had the lowest risk.  The team however did not identify reduced risk for squamous cell carcinoma.

According to co-author, Fengju Song, a postdoctoral fellow in dermatology, the discovery could help prevent cancers in the future. “Daily dietary factors with even small protective effects may have great public health impact,” Song said in a statement.  “Our study indicates that coffee consumption may be an important option to help prevent basal cell carcinoma.”

“This is yet another study that says there is some benefit in terms of skin cancer for drinking caffeinated beverages,” said Paul Nghiem, associate professor at the Fred Hutchinson Cancer Research Center and University of Washington. “And if you do so, it is another reason to enjoy them. But it is a pretty small effect compared to known things, like getting a cancer detected and cut out early, avoiding sunburns, etc.” He said they are also looking into whether caffeine should be added to sunscreen to increase its effectiveness against skin cancer.

“It's a very interesting study. It's the first one that has implicated basal cell carcinoma reduction in coffee drinkers,” said Allan Conney, director of the Susan Lehman Cullman Laboratory for Cancer Research at Rutgers, The State University of New Jersey. “I am surprised to see that there was no effect on squamous cell carcinomas, which the animal models would have predicted.” Conney says the biology of these types of skin cancer is different and might explain why caffeine appears to have a protective effect against some types of skin cancer and not others.

Basal cell carcinoma is most common in people with light hair and green or blue eyes, and can manifest itself as a skin sore that bleeds and doesn't heal, though it rarely spreads to other parts of the body. They are the most common form of skin cancer in the United States, with about a million new cases arising each year. Researchers will have to do more work to identify the mechanism behind the reduced cancer risk, Song added. Previous studies have shown coffee drinkers tend to have fewer incidences of breast, uterine, prostate and colon cancers, but the beneficial effects are not seen in people who drink decaffeinated coffee.