There may be a down side to that daily aspirin tablet. New research shows that men who take a pill for its many health benefits might also be doubling their risk of melanoma.

Northwestern University researchers collected medical record data from patients with no history of melanoma, a type of skin cancer. The study included only patients who had taken either 81 milligrams or 325 milligrams of aspirin for at least a year. A typical aspirin tablet for an adult is 325 milligrams.

Among a group of nearly 1,200 patients who took aspirin, the rate of melanoma diagnoses was slightly more than 2 percent. That’s compared with a melanoma rate of about 1 percent among people who didn’t take a daily aspirin.

Daily aspirin therapy is used to help prevent heart attacks and is thought to lower the risk of prostate, colon, gastric and other cancers. About half of people age 65 and over take aspirin daily, a 2005 study found.

Researchers don’t know why aspirin may increase melanoma vulnerability in men more than women. One possibility is that men have fewer enzymes that protect the body than women, which could lead to more cellular damage and contribute to melanoma development.

The findings do not mean that aspirin therapy should be stopped if you’re trying to prevent a heart attack, the researchers stressed. But men who use aspirin to protect other aspects of their health should stay away from tanning beds, get knowledgeable about sun exposure and get regular skin checks from a dermatologist — especially if they have an elevated risk of skin cancer.

Remember, if you’re popping an aspirin for its heart benefits, don’t forget to be sensible about being safe in the sun.