New research reveals yet another health benefit of coffee. Besides protecting your heart, brain, liver, and teeth, coffee may drastically reduce your risk of malignant melanoma, the deadliest form of skin cancer and the fifth most common type of cancer among men.
This finding comes from a National Cancer Institute study of almost 450,000 non-Hispanic white men and women, the demographic that runs the greatest risk of this disease. Those who drank four or more cups of coffee per day slashed their melanoma risk by 20 percent. This was even after the researchers controlled for other factors that could impact skin cancer risk, such as age, physical activity, smoking, and the amount of UV exposure a person likely gets based on geographical location. Interestingly, only regular coffee — not decaf — had an effect on melanoma risk.
Although people who consumed one, two, or three cups of coffee every day had a very slight decrease in melanoma risk over non-coffee drinkers. It was only with four or more cups that the risk reduction became significant, says lead researcher Erikka Loftfield. While four cups of coffee might sound like a lot, keep in mind that we’re talking about real cups here — 8 ounces each — not your jumbo ceramic mug or a Venti from Starbucks.
Loftfield’s team did not pinpoint the reason why coffee may guard against melanoma. However, several earlier studies have found that coffee’s anti-cancer effects come from its abundance of antioxidants and anti-inflammatory compounds. One of those is caffeine, which might explain why decaf didn’t do the trick in this study. "Caffeine, or another compound that is more abundant in regular coffee than decaffeinated, could be related to these findings," Loftfield says.
Previous research has also found that caffeine has a similar effect on other forms of skin cancer. A Harvard study from 2012 showed that men who drank more than three cups of caffeinated coffee a day were 10 percent less likely to develop basal cell carcinoma, the most common kind of skin cancer. Rutgers University researchers did a study in 2011 in which they applied caffeine topically to the skin of mice and then exposed them to ultraviolet radiation to emulate sunlight. The caffeine-coated mice developed far fewer cases of squamous cell carcinoma, another form of skin cancer. The researchers say that caffeine works by inhibiting a particular protein that otherwise enables UV-damaged skin cells to become cancerous. Essentially, caffeine acts as a cellular sunscreen.
Despite all of these findings, coffee alone will never spare you from skin cancer. Keep smearing on the sunscreen whenever you’re outside for 15 minutes or more.