UV radiation is a stream of invisible high-energy rays coming from the sun that can damage the genetic material of skin cells. The more time you spend in the sun, the greater your risk of developing skin cancer.

Be Safe in the Sun
Children are especially at risk. A history of five or more severe sunburns during adolescence more than doubles the risk of melanoma, according to a study published in the April 29, 1999, issue of The New England Journal of Medicine, by Barbara A. Gilchrest, MD, and colleagues in the Department of Dermatology at Boston University. Scientists also believe people may receive up to 80 percent of their life?s total exposure to UV light by the age of 18.

The thinning ozone layer allows more of the sun?s ultraviolet radiation to reach the earth. In addition, people are spending more time in the sun and wearing less clothing. Although anyone can get melanoma, people who freckle or burn before tanning, have fair skin or blond, red, or light brown hair, spend a lot of time outdoors, and have a family history of skin cancer are especially at risk.

People should protect their skin year-round with proper clothing, a hat, and sunscreen with a skin protection factor (SPF) of 15 or higher. "Sun-seeking behavior is a problem, but we do want to discourage people from being inactive and spending too much time indoors. It is healthy to go outside and be active. Just avoid exposure to the sun at its most intense [during the middle of the day], and when outside, wear protective clothing, a hat, sunglasses, and plenty of sunscreen," said Martin Weinstock, MD, PhD, director of the dermatoepidemiology unit at Brown University and chairman of the American Cancer Society?s (ACS) Skin Cancer Advisory Group.

Avoid Sun When Ultraviolet Rays are Most Intense

• Avoid outdoor activities when the sun?s rays are most intense. Limit time spent in the midday sun (between 10:00 a.m. and 4:00 p.m.). Practice the shadow rule and teach it to children: If your shadow is shorter than you, the sun?s rays are at their strongest.
• UV rays can pass through water, so don't assume you're safe if you're in the water and feel cool. Be especially careful on the beach and in the snow, because sand and snow reflect sunlight and intensify the amount of UV radiation you can receive.

If you plan to be outdoors, you may want to check the UV Index in your area. The UV Index, a rating from 0 to 10+, can usually be found in your local newspaper, on TV, or in radio news broadcasts. It is also available on the Internet at the National Weather Service Climate Prediction Center's home page.

When in the Sun, Cover Up.
Wear loose, comfortable clothing that protects the arms, legs, and body. Dark colors provide more protection than light colors, and fabric with a tight weave is the best. If you can see light through a fabric, UV rays can hit your skin, and dry fabric is generally more protective than wet fabric.

"Remember, sunscreen is not to be worn in lieu of clothing," cautions Allan Halpern, MD, chief of dermatology services at Memorial Sloan-Kettering Cancer Center in New York City and vice chairman of the ACS?s Skin Cancer Advisory Group.

Recently, a number of companies have begun selling protective sun-suits and other clothing for children with a special "sunblocking" fabric, which is essentially a tightly woven nylon. The items offer the convenience of a bathing suit, but cover more of the body.

A hat is essential to protect sun-sensitive areas like the ears, nose, and scalp. Hats with wide brims that shade your face, neck, and ears are recommended. If you choose a baseball cap instead, protect your face, neck and ears with a generous amount of sunscreen with an SPF of 15 or higher. Research has shown long hours in the sun without adequate eye protection increase the chances of developing cataracts and some types of eye cancers. The ideal sunglasses do not have to be expensive, but should carry a label that says they block 99 percent to 100 percent of UVA and UVB radiation. Check the label to be sure. UV protection comes from an invisible chemical applied to the lenses, not from darkness of the lenses. Children need smaller versions of real, protective adult sunglasses, not toy sunglasses.

Teach children the ACS?s simple "Slip! Slop! Slap!"? rule for spending time outdoors:

• Slip on a shirt,
• Slop on sunscreen (SPF of 15 or higher),
• Slap on a hat, and
• Wrap on sunglasses.