Men's Skin May Be More Sun-Sensitive

Skin cancer due to sun exposure appears faster — and is more severe — in males than in females, mouse studies show.

It's well known that men are more likely to get skin cancer than women are. Men get twice the overall number of skin cancers and three times more squamous cell carcinomas than women do, notes Tatiana M. Oberyszyn, Ph.D., assistant professor of pathology at Ohio State University in Columbus.

Why? Researchers usually say this is because men are more likely than women to have outdoor jobs — and that they are less likely to protect their skin with sunscreen, shirts, and hats. Oberyszyn wondered whether this is true.

To test the theory, Oberyszyn's team exposed a breed of hairless mice to ultraviolet rays from a sun lamp. The mice underwent eight- to 10-minute tanning sessions three times a week for six months. That was enough to give both male and female mice skin cancer.

"We found males got skin tumors earlier, got more of them, and more of the tumors were severe," Oberyszyn tells WebMD.

What was going on? Tests of male and female mouse skin turned up a surprising finding.
The male skin cells carried fewer antioxidants than the female skin cells.

"Our skin is exposed to both physical and environmental stimuli all the time," Oberyszyn says. "Our immune system keeps us healthy. But the immune system can overreact sometimes. You get overproduction of reactive oxygen species — and antioxidants protect against this."

The researchers are now looking at human skin to see if men really are like mice.

"We think male skin is just more sensitive," Oberyszyn says. "Perhaps men need something that would provide with them more antioxidants — maybe diet, maybe a skin cream. In addition to sunscreen, maybe men need to pay more attention to their skin than women do. It is not a cosmetic thing; it really is a health issue."

Marianne Berwick, PhD, is the head of cancer epidemiology and prevention at the University of New Mexico in Albuquerque. Berwick agrees with Oberyszyn that there's a huge difference between men's skin and women's skin.

However, she notes that men really do get more exposure to cancer-promoting ultraviolet light than women do.

"This current study is solid, good research, but it is not the whole story," Berwick says. "I would hate to see people taking more antioxidants or putting it on their skin because of this. The differences between male and female skin are due to intrinsic biology and are not simply a matter of antioxidants themselves."

The Oberyszyn study appears in the April 1 issue of Cancer Research.

By Daniel DeNoon
Reviewed by Louise Chang, M.D.
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