Caffeine and exercise may reduce the risk of developing skin cancers caused by exposure to the sun, according to a new study on mice.
"I believe we may extrapolate these findings to humans and anticipate that we would benefit from these combination treatments as well," Dr. Yao-Ping Lu is associate research professor of chemical biology and director of skin cancer prevention at the Rutgers Ernest Mario School of Pharmacy in Piscataway, New Jersey, said in a statement.
The findings, presented at the American Association for Cancer Research (AACR) Annual Meeting 2012 in Chicago on Tuesday, show that fat and tumor growth are associated, and the combination of exercise and caffeine may not only prevent skin cancer but also inflammation linked to other obesity-related cancers.
The study consisted of four groups of mice that were all exposed to UVB radiation, a component of sunlight associated with skin cancer risk. The control group were given plain water and no exercise wheel, another group had water mixed with caffeine and no exercise wheel, a third group had plain water and an exercise wheel, and a fourth group had caffeine mixed water as well as well as an exercise wheel, and all groups undergone 14 weeks of treatment.
While caffeine or exercise alone had some positive effects, researchers found substantially more benefits from the combination of caffeine and exercise on skin cancer risk.
The findings show that mice in the caffeine and exercise group had 62 percent fewer non-melanoma skin tumors and tumors that were 85 percent smaller than those to the control group.
There were 27 percent fewer tumors and a 61 percent reduction in tumor size in the caffeine without exercise group, and 35 percent fewer tumors and a 70 percent reduction in tumor size in the exercise without caffeine group.
In an another set of experiments where mice were on a high-fat diet of omega-6 fatty acid-rich foods, researchers found that the caffeine plus exercise group had 92 percent drop in levels of inflammatory markers as well as reduced cancer development and tumor size.
Scientists from the latest study suggest that there may be a link between fat, inflammation and cancer. They explained that fat tissue secretes inflammatory compounds, so reduced fat means less inflammation, which has been previously linked to increased skin cancer risk.
The study was funded by the National Institutes of Health.