Caffeine and exercise together may be up to four times as protective against ultraviolet light induced skin cancer than either alone.
A recent laboratory study found that topical application of caffeine 30 min before ultraviolet-B (UVB) exposure inhibited the formation of thymidine dimers by 70 to 80 percent — thymidine dimers are the genetic basis for UVB-induced skin cancer.
Another study found that the combination of caffeine and exercise boosted elimination of ultraviolet light damaged cells in mice. Disposal of these cells would decrease the risk of future skin cancer.
The study compared the effects of caffeine, exercise, and the combination of both in three groups of mice whose exposed skin is prone to skin cancer.
One group of mice drank the equivalent of one to two cups of coffee a day in the form of caffeinated water. Another group ran on an exercise wheel, and a third drank the caffeinated water and ran on the wheel. All of the mice were exposed to UV radiation.
Some of the mice’s damaged skin cells were eliminated through apoptosis — a programed, choreographed process that occurs when damaged cells die. The rate of apoptosis among these damaged cells was highest in the third group that drank caffeine and exercised.
Of course, caffeine and exercise are not a substitute for wearing sunscreen. But it does justify splurging on a double latte today.
Just don’t bring your Starbucks venti coffee with you on the gym treadmill in the morning; that drives me nuts.
Photo credit: FCC, Brian Cribb
Lu, Y-P., Lou, Y-R., Peng, Q-Y., Xie, J-G., Nghiem, P., and Conney, A. H. (2007) Proc. Am. Assoc. Cancer Res. 48:821