Sun Can Cost You More Than the Skin off Your Nose
American Forces Press Service
WASHINGTON, Sep. 10, 2001 Maybe you've had your last sunbath for the year, but don't drop your guard. Summer's just the highest-risk season for sun-damaged skin. Fact is, your face and hide are at risk when the sun's up.
While you bask in those compliments about your great tan, here are the usual health carps about tans: You injured the largest organ of your body. You've sped the day you will be a leathery prune. You upped your chances of contracting skin cancer.
You tan when your body begins to find ultraviolet-B radiation intolerable. The most potent UVB source is sunlight for most people. Your body's defense is to create UVB-absorbing melanin -- skin coloring. You get darker as the exposure continues. The defense is not perfect; that's why people burn.
Repeated tanning and burning damage skin cells and wear out the skin's natural immunity and repair systems over time. As UVB compromises the skin's ability to protect and fix itself, damaged cells and tissues can wreak havoc. If you're unlucky, moles, rashes and other lesions erupt. If the only luck you have is bad, you're looking at lethal malignant melanoma -- skin cancer.
Then there's ultraviolet-A radiation. UVA plays no role in tanning and burning, but it penetrates the skin deeper than UVB rays and also damages the skin's immunity and repair systems. The skin dries, loses flexibility and wrinkles in time; the risk of cancer increases.
On any given day of the year, the sun's most intense UVB radiation arrives at midday. While people usually know to take precautions at high noon, they may not realize the sun's ultraviolet energy is almost all a constant, imperceptible, day-long, year-round stream of deep- penetrating UVA radiation. Keep that in mind when you've been out long enough to catch a tan.
People of color may have a protective head start against UVB, but they too can darken and burn -- it may just take longer. Further, skin color offers no protection against UVA.
Fortunately, protection is easy. Stay indoors. Stay out of the sun. When those aren't options, your best defenses are the same as in summer: sunscreens and clothes.
Sunscreen racks may be gone from stores. Sunscreen chemicals, however, are increasingly easier to find year- round in commercial cosmetics, skin creams and lotions, and lip balms.
Sunscreen protection is expressed as a "sun protection factor." The SPF multiplies the time you can be exposed to UVB safely. If your normal limit in the sun is 10 minutes, a UVB sunscreen rated at SPF 15 would help protect you for 2.5 hours.
There's no standard way to express UVA protection, such as an SPF, so it's possible your sunscreen and cosmetics offer none. Read the ingredients list. Common screens such as padimate and homosalate only stop UVB. If your product contains an effective UVA sunscreen such as benzophenone and avobenzone, the maker probably trumpets that fact.
Three year-round sunscreen rules: Use it liberally. Use it often. Apply it to exposed skin at least 20 minutes before going outside. According to some medical researchers, sunscreens fail because people skimp. After all, the stuff's expensive, and people get distracted and are rushed.
- Follow the product instructions. While "apply generously" doesn't say how much is enough, it's a hint that the stingy little dab on your fingertip that you've been using is not enough to protect your whole face.
- Wash your hands? Reapply sunscreen. Wash your face? Reapply. Sweat? Reapply. Wipe your brow? Reapply. SPF protection time's up? Reapply.
- Sunscreens don't work until they set, generally in 20 to 30 minutes. If your normal sun limit is 10 minutes but you apply your SPF 3000 screen only after you're on that lift up the sunny ski slope, you may be overdosed on UVB before you reach the top.
- All clothing can provide some protection against UVB rays and also some against UVA if layered or heavy. Yardsticks: One layer of T-shirt fabric provides minimal protection against UVB and none against UVA. Tightly woven fabrics protect better than loose weaves against both UVB and UVA. Dry protects better than wet. The Centers for Disease Control estimate blue denim jeans have an SPF of 1700! The jury's still out on whether fabric color makes any protective difference.
- It's smart to wear a hat and sunglasses in the sun outdoors, regardless of the season. Sunglasses should say they filter both UVA and UVB. If they don't say or they filter only UVB, consider them good only for fashion statements.
- Don't use tanning booths and beds. UVB radiation isn't safe whether it's from Mr. Sun or bulbs. Look pasty from October to June? Get over it.