Sun exposure is the leading risk factor for developing melanoma. And there's evidence that alcohol consumption is linked to an increased risk of skin cancer, too.
Part of the explanation is that when people drink, they tend to be more lackadaisical: They're less likely to apply sunscreen and more likely to spend too much time in the sun, be it at the beach or pool. But this isn't the whole story.
"The research suggests that alcohol reduces the amount of time you can spend in the sun before you get a burn," explains Aaron White, a senior scientific adviser with the National Institute on Alcohol Abuse and Alcoholism.
One line of evidence comes from a small study of healthy men conducted in Germany. Researchers measured how much UV light it took to burn their skin after the men consumed about three drinks. It turns out, after drinking alcohol, "the amount of UV light it took to burn the skin was significantly less," White explains.
He says the result is surprising, "because it tells us that alcohol increases the risk of getting a sunburn — not just because people don't tend to put on sunscreen."
It's not exactly clear why this happens. But scientists have a hunch. As part of the study, the researchers measured the concentration of carotenoids in the participants' bodies. Carotenoids are the yellow, orange, and red pigments that are produced by plants. When we consume carotenoids from fruits and vegetables, these pigments exert an antioxidant effect in our bodies that may help protect against the damage done by the UV light.