AP National Writer

Summer's almost here and that means many teens and college students will be outside a lot, particularly after a wet spring in much of the country. But how many will use sunscreen?

Dr. James Spencer, a dermatologist from the Mount Sinai School of Medicine in New York and a spokesman for the American Academy of Dermatology, says not nearly enough.

A Boston University survey of young Americans, ages 12 to 18, found that only a third regularly use sunscreen. The survey, published last year in the journal Pediatrics, also found that 83 percent had at least one sunburn the previous summer and 36 percent had three or more.

And it's not all happening outside, or in summer.

Ten percent of all those surveyed _ and 14 percent of girls _ also said they'd used indoor tanning. Spencer says those numbers only increase in the college years, especially for young women.

No big deal? Think again, says Spencer, who's got some advice for those who spend time in the sun and in tanning salons.


Q: Does it really matter if I get a sunburn every once in a while?

A: Yes, it does. The likelihood of developing skin cancer and wrinkles increases with the more sun you get. But even just a few bad sunburns increases the risk of developing melanoma, the most deadly skin cancer.

This is particularly true when you're younger. It seems that, before age 20, our skin is much more sensitive to the harmful effects of the sun than when we're older.


Q: What is melanoma? And how is it different from other skin cancers?

A: Cancer is the uncontrolled growth and spread of cells. As the cancer cells grow and spread they replace normal cells, destroying their function much like weeds overgrowing a garden.

Melanocytes are cells in our skin that produce the brown pigment melanin that gives our skin its color. Melanoma is a cancer of the melanocytes.

There are other types of cells in our skin, too, and growth of abnormal types of these cells gives rise to other kinds of skin cancer.


Q: Is there any way to tell if my skin has been damaged?

A: If you've tanned or burned, you've already damaged your skin. A burn is a clear sign of damage. A tan, in fact, is the body trying to protect itself from more damage.


Q: If I only tan and don't burn, does that mean I won't get skin cancer?

A: No. When our skin is damaged by ultraviolet radiation from the sun, the skin senses that damage and makes the brown pigment melanin to protect itself from more harm. Melanin blocks the ultraviolet rays from entering the skin.

But to develop a tan, you must damage your skin first. So there is no way to tan safely.


Q: Is tanning at indoor salons any safer or better for my skin?

A: No. Sunlight contains two types of ultraviolet light: UVA and UVB. The UVB is primarily responsible for a sunburn. But both types of UV radiation cause wrinkles and skin cancer.

Indoor tanning salons use devices that give off ultraviolet radiation _ a mixture of both UVA and UVB that's meant to mimic the sun.

So, whether you tan at the beach or in the tanning salon, you're damaging your skin.


Q: What does the abbreviation SPF on sunscreen mean? And which SPF would you recommend?

A: SPF stands for Sun Protection Factor and is measured by how long it takes to develop a sunburn.

Normally, if it takes you 30 minutes to burn in noontime sun, then with SPF 2, it would take twice as long, or one hour. With SPF 4, it would take two hours.

In general, an SPF of 15 or higher is enough. But we've learned that sunscreens don't stay on the skin very long _ and are gone in about two to four hours, especially if you're swimming or exercising. So after four hours, it wouldn't matter if the sunscreen were SPF 800, because it'd no longer be on your skin.

But again, there's more to worry about than just protecting yourself from sunburn. Since both types of UV radiation cause wrinkles and skin cancer, it's very important for your sunscreen to have broad protection against both types of ultraviolet light _ UVA and UVB. So read the labels carefully.


Q: Are creams and other products that produce a fake "tan" safe for your skin?

A: Overnight or instant "tans" are dyes that color the outermost layer of the skin. The dye usually lasts four to five days and is completely harmless. But remember, it does not protect you from the sun.


Martha Irvine can be reached at mirvine(at)ap.org