Coffee, exercise may decrease risk of skin cancer

A cup of coffee and a morning workout may significantly reduce your risk of skin cancer, according to a new animal study presented Tuesday at the annual meeting of the American Association for Cancer Research in Chicago.

The researchers, from Rutgers Ernest Mario School of Pharmacy, wanted to evaluate the effects of both caffeine and exercise on mice that were at high risk for developing skin cancer. Previous research has shown that mice given either caffeine or an exercise wheel had a reduction in skin cancers.

The researchers exposed high risk mice to ultra violet B light, which is known to cause skin cancer, and then gave one group of mice caffeine (in water), one group an exercise wheel, a third group caffeine plus an exercise wheel, and a control group plain water for 14 weeks.

Results showed that mice who got a dose of caffeine and exercised on the wheel had 62 percent fewer non-melanoma skin cancers. The size of those tumors also decreased by 85 percent compared with the mice that did not get caffeine or exercise.

"We found that this combination treatment can decrease sunlight-caused skin cancer formation in a mouse model," saidYao-Ping Lu, associate research professor of chemical biology and director of skin cancer prevention at the Rutgers Ernest Mario School of Pharmacy in Piscataway, N.J.

The mice who only had caffeine (and no wheel) had a 27 percent reduced risk of skin cancers and those that exercised only had a 35 percent reduced risk. Both groups had a significant reduction in the size of tumors compared to the controls.

They also found that mice given caffeine exercised 40 percent, suggesting that coffee may make mice (and people) inclined to exercise longer and harder. Finally, those in the caffeine plus exercise group experienced a reduction in fat and had as much as 92 percent reduced levels of inflammatory markers. Fat tissue secretes a lot of inflammatory chemicals, so less fat would lead to a less inflammation. This may be the link to skin cancer, Lu said. Inflammation has been associated with increased risk of skin cancer.

The authors believe that the combined effects of exercise plus caffeine may be able to ward off skin cancer and also prevent inflammation related to other obesity-linked cancers.

"I believe we may extrapolate these findings to humans and anticipate that we would benefit from these combination treatments as well," Lu added.