The combination of exercise and caffeine increased destruction of precancerous cells that had been damaged by the sun’s ultraviolet-B radiation, according to a team of researchers at Rutgers University.
Americans suffer a million new cases of skin cancer every year, according to the National Cancer Institute.
In mice there is a protective effect from both caffeine and voluntary exercise, and when both are provided — not necessarily at the same time — protection is even more than the sum of the two, said Dr. Allan H. Conney of the laboratory for cancer research at Rutgers.
“We think it likely that this will extrapolate to humans, but that has to be tested,” Conney said in a telephone interview.
Nonetheless, he added, people should continue to use sunscreen.
Exposing the mice to ultraviolet-B light causes some skin cells to become precancerous.
Cells with damaged DNA are programmed to self-destruct, a process called apoptosis, but not all do that, and damaged cells can become cancerous.
The researchers report in Tuesday’s issue of Proceedings of the National Academy of Sciences that they studied hairless mice in four groups. Some were fed water containing caffeine, some had wheels on which they could run, some had both and a control group had neither.
“The most dramatic and obvious difference between the groups came from the caffeine-drinking runners, a difference that can likely be attributed to some kind of synergy,” Conney said.
Compared with the control animals, those drinking caffeine had a 95 percent increase in apoptosis in damaged cells. The exercisers showed a 120 percent increase, and the mice that were both drinking and running showed a nearly 400 percent increase.
Just what is causing that to happen is not yet clear, though the researchers have several theories.
“We need to dig deeper into how the combination of caffeine and exercise is exerting its influence at the cellular and molecular levels, identifying the underlying mechanisms,” Conney said.
“With an understanding of these mechanisms we can then take this to the next level, going beyond mice in the lab to human trials,” he said. “With the stronger levels of UVB radiation evident today and an upward trend in the incidence of skin cancer among Americans, there is a premium on finding novel ways to protect our bodies from sun damage.”
Conney said the researchers were originally interested in the effects of green tea in preventing skin cancer and were doing tests on regular and decaffeinated teas.
They found the regular tea had an effect, but not the decaffeinated brew.
And, he said, researchers also observed that mice drinking caffeine were more active than those that didn’t get it, so they decided to study the effects of exercise too.
Related Url: www.msnbc.msn.comWhen you snack, you can fill in nutritional gaps, boost your intake of fruits and vegetables, keep your mood on an even keel, and help with appetite and weight control.
Every diet offers room for treats, and there’s no reason to feel guilty about en
Since squeezing fitness pursuits into an already busy day isn’t easy, it makes sense to use the lunch hour for double duty. Work out, then eat. Trouble is, there’s not much time for both. So save time by preparing a quick, high-caliber meal the night befo