Sun safety: Facts about skin cancer and tips on preventing it

With summer upon us, Yale Medical Group physicians have an urgent warning: Be sun smart. Practicing good sun protection, including the use of sunscreen, could save your life, they say.

"You don't want to go crawl under a rock or hide in the basement," says dermatologist Dr. David Leffell, CEO of Yale Medical Group and a member of Yale Cancer Center. "You want to be active and that usually is best done outdoors — simply use moderation and common sense."

Leffell recommends the following:

  • Avoid the sun between 10 a.m. and 4 p.m. Leffell says, "That means stay in the shade and certainly don't schedule your kids' ball games at high noon."
  • Wear a broad-brim hat, not a baseball cap, as attractive as they may be. "The majority of skin cancers are on the head and neck, so a brimmed hat that protects the ears as well as the nose is important," Leffell explains.
  • Wear sun-protective clothing. "There is now sun protective clothing that looks like normal clothing, not like a prison uniform," he says. "They have a tight weave that is chemically treated, and they actually are UPF-rated, meaning 'ultraviolet protective factor'-rated."
  • Apply sunscreen every couple of hours while you're active outdoors and after swimming. "It is said that a shot glass full of sunscreen should cover the sun exposed parts of the body," notes Leffell.
  • Wear sun protective eyeglasses to prevent cataracts.

Leffell notes that there is a great deal of research going on at Yale Medical Group into skin cancer and how to prevent it. He answered the following questions recently on the Yale Medical Group website. (www.yalemedicalgroup.org)

Have we learned anything new about skin cancer prevention in the last few years?

We know from experimental studies that if you block ultraviolet (UV) radiation from skin, the cells that have been mutated by previous sun exposure may actually regress. This is scientific proof that it is never too late to start a program of protection against UV.

Skin cancer is on the rise. Is it limited to any one demographic?

A new study shows that men over age 50 have the greatest increase in deaths from melanoma. Another group of special concern are young women. It appears in my practice, as well as in the practices of others who specialize in skin cancer, that more and more people in their 20s and 30s are developing basal cell cancer and squamous cell cancer, which are slow-growing cancers that are completely different than melanoma and easy to treat if they're caught early.

Why are more young people being diagnosed?

We don't know for sure. It could relate to more sun exposure or increased use of tanning parlors. It is also true the majority of sun exposure occurs in childhood, so it is critical that parents take special precautions to protect young children. The genetic damage caused by the sun accumulates over time like compound interest, so any protection that can be provided in childhood will pay off later.

Does sunscreen provide adequate protection?

Sunscreen has evolved dramatically over the years. I am a consultant to Coppertone, and work with their scientists on the development of sunscreen products and ways to make them more attractive to individuals, because we know that using sunscreen is a nuisance. There are now many products that go on more easily and leave your hands less sticky. But the bottom line is that there is a huge amount of benefit provided by sunscreen. It does prevent the damaging ultraviolet rays from injuring the skin. It is important to look for broad-spectrum sunscreens that provide protection against UVA and UVB rays.

What do you think about recent comments alleging a relationship between vitamin A in sunscreen and increased risk of melanoma? 

That's an interesting observation. We really need to see the data before commenting, since it is well known that vitamin A derivatives are actually used to treat certain cancers. In the meantime, sunscreen use should continue as an important part of a comprehensive sun protection program.

There are so many sunscreens. How do you choose the best one?

It's really a matter of reading the label. You want a sun protection factor (SPF) of 30 or higher to protect against UVB waves, which typically are cancer-causing even though they have less of an effect on aging of the skin. You also want the sunscreen to have UVA protection to protect against ultraviolet A waves, which penetrate into the dermis and cause premature aging of the skin. Some recent evidence suggests that UVA also can play a role in causing certain skin cancers.

NOTE: David Leffell is CEO of Yale Medical Group, a member of Yale Cancer Center and chief of dermatologic surgery and cutaneous oncology at Yale School of Medicine. He is the author of "Total Skin: The Definitive Guide to Whole Skin Care for Life," and has a website devoted to helping people learn about skin cancer prevention and treatment: www.totalskinandhealth.com.

Click here to read the story of one young Yale employee's battle against melanoma.

— By Helen Dodson