Sunscreens

Think that tan looks good on you? A suntan is actually the skin’s reaction to an injury inflicted by ultraviolet light rays. Here are some facts about protecting yourself.

“Broad spectrum” sunscreens are best.

Use sunscreen products that offer protection against both ultraviolet B (UVB) light, which is primarily responsible for tanning and burning, and ultraviolet A (UVA) light, which penetrates deeper into the skin. The American Academy of Dermatology recommends using screens with a minimum sun protection factor (SPF) of 15.

A rule of thumb for gauging the sun’s intensity is that the rays are strongest when your shadow is shortest. But to take out the guesswork, you can check the ultraviolet radiation levels in your city daily, courtesy of the Environmental Protection Agency’s UV index.

Sunscreens are not a bulletproof vest.

Sunscreens reduce, but do not prevent, the exposure of your skin to damaging ultraviolet rays. Wearing SPF 15 screen in the sun for 15 minutes is roughly equivalent to spending one minute baking with no protection whatsoever. The zinc oxide or titanium dioxide in total-protection screens (formerly known as sunblocks), by contrast, provide a physical barrier between UV and your skin. If you think cotton T-shirts are the way to go, think again: They provide protection only around SPF 5.

There are over 1 million good reasons to be cautious about sun exposure.

If you’re getting tanned at all, you’re being exposed to UV radiation; and if you’re exposed to UV radiation, you are increasing your risk of skin cancer. Skin cancer is the most common of all cancers, representing more cases than prostate, breast, lung, colon, uterus, ovaries and pancreas cancers combined. According to the American Cancer Society, most of the 1 million cases of nonmelanoma skin cancer diagnosed every year are sun-related. ACS estimates that over 62,000 new cases of melanoma, the most serious skin cancer, will be diagnosed in 2006 in the U.S. Though treatment and survival rates are excellent given early detection, melanoma will still claim nearly 8,000 lives this year.

If preventing skin cancer is not enough motivation, there are other benefits to using sunscreen.

Sunscreens help prevent the premature aging of skin from sun exposure; “photoaged” skin tends to be wrinkled and leathery, and has irregular pigmentation. When taking medications that sensitize the skin to sunlight, high SPF sunscreens are helpful though not a total guarantee of protection. Sunscreen also prevents freckles.

Small children need extra protection.

“Children under the age of 6 months have very sensitive skin, and sunscreens are potentially irritating to them,” says Dr. Sandra Read, a dermatologist in Washington, D.C. “They are better protected by staying out of the sun, seeking shade, avoiding peak hours of sunlight, and using protective clothing such as hats and long sleeves.” Dr. Read also warns that adults and children should not be fooled by an overcast day, since a full 80 percent of the sun’s radiation still penetrates the clouds.

People with dark skin need sunscreen, too.

“Having more of that pigment, or melanin, is like having a little bit of sunscreen in your skin,” says Dr. Read. “While it may help protect you from an acute burn, it does not protect you from skin cancer or from photoaging. People say, ‘I have a base tan—I’m protected.’ What are you protected from? You might not get a painful first-degree burn, but you’re going to be out in the sun more, so you’re more susceptible to skin cancer.”

The key ingredient of many sunscreens is PABA, or para-aminobenzoic acid, which protects the skin by absorbing ultraviolet light. But PABA has to bind to the skin to be fully effective, and that takes about half an hour once the screen has been applied.

To learn more about sun exposure and skin cancer, visit the "Sun Safety" pages at the American Cancer Society. Also search our articles here at MSN Health & Fitness and at the American Academy of Dermatology.

Find more on MSN Health & Fitness:

• All About Skin Care
• Checking for Signs of Skin Cancer
• Talk About It: What's the Best Sunscreen?
• Summer Health Checklist