The sun radiates light to the earth, and part of that light consists of invisible ultraviolet (UV) rays.But not all of the sun's rays are pleasing. Ultraviolet (UV) light, the invisible but intense rays of the sun, damages your skin. Some of those harmful effects — such as suntan or sunburn — are visible right away. But other skin changes, including liver spots or deep wrinkles, appear and worsen over time. With repeated sun exposure, the skin damage can even progress into cancerous tumors.

When these rays reach the skin, they cause tanning, burning, and other skin damage.UV rays react with a chemical called melanin that's found in most people's skin. Melanin is your first defense against the sun. It absorbs dangerous UV rays before they do serious skin damage. As the melanin increases in response to sun exposure, the skin tans. But even that "healthy" tan may be a sign of sun damage. The risk of damage increases with the amount and intensity of exposure.

Unprotected sun exposure is even more dangerous for kids with:

• moles on their skin (or whose parents have a tendency to develop moles)
• very fair skin and hair
• a family history of skin cancer, including melanoma.Extended and repeated exposure to UV light can cause noncancerous (benign) and cancerous skin tumors.
• Over the years, your skin naturally begins to show signs of aging. For example, you may notice more wrinkles and thinner, more fragile skin. Exposure to UV light can accelerate these changes and make you appear older than you are. Skin changes caused by the sun are called photoaging.

Sunburn can easily be prevented through the use of sunscreen, clothing (and hats), and by limiting solar exposure, especially during the middle of the day. The only cure for skin burn is slow healing, although skin creams can help.In the winter time, windburn is commonly confused with a sunburn, with typically milder symptoms.

In response to the increasing incidence of skin cancer, cataracts, and other effects from exposure to the sun's harmful rays, the National Weather Service (NWS), the US Environmental Protection Agency (EPA), and the Centers for Disease Control and Prevention (CDC) collaborated on a sun awareness information program.

An important part of this program is the Ultraviolet (UV) Index, developed by the National Meteorological Center of the National Weather Service.

A collaborative approach involving parents, sports coaches, teachers, health professionals and youngsters may motivate teens to better protect themselves from the sun's harmful UV rays, the results of a new study suggest.

The findings are integral to public health efforts to reduce the incidence of skin cancer, in light of previous research showing that children are less likely to use sunscreen or other sun-protective measures as they reach high-school age and young adulthood.

To change teenager's sun protection habits, we need to "create an environment around the teen where people are all using and talking about skin protection," study author Dr. Ardis L. Olson, of Dartmouth Medical School, in Lebanon, New Hampshire, told Reuters Health.

Increased sun exposure raise the risk of melanoma, the most deadly and increasingly common form of skin cancer. But stressing this point may not be very effective among image-conscious teenagers, according to Olson.

"We won't get anywhere talking about skin cancer to kids," she said, because the idea of skin cancer is "too remote" to them. Instead, teens should be cautioned about "premature wrinkling" and "what a bummer it is to get a sunburn and not be able to do what...you want to do," she said.

In the "SunSafe in the Middle School Years" study, Olson and her colleagues recruited adults and teen peer leaders in 10 communities to educate middle schoolers about the importance of protecting themselves from the sun.

Rather than relying on classroom instruction alone, the SunSafe participants used poster contests, buttons and a variety of other means to promote their sun-safety message. Students in the SunSafe communities were also given the opportunity to view their own and others' faces in a portable Dermascan device, which allows people to see changes in their skin that are invisible in normal light.

The researchers afterwards conducted annual observations of teenagers, including a group that had not participated in the SunSafe intervention program, at community beaches and pools. Altogether, their study involved 1,927 students in 6th to 8th grade.

Two years after the SunSafe program, students in the intervention group showed better sun protection behaviors than teens who had not participated in the SunSafe program, Olson's group reports in the January issue of Pediatrics.

On average, SunSafe teens protected about two thirds (66 percent) of their body surface area, compared with about 57 percent of the body surface area protected by other teens.

"This new ecological approach shows promise in changing adolescent sun protection behaviors and reducing skin cancer risks," the researchers conclude.

We all need some sun exposure; it's our primary source of vitamin D, which helps us absorb calcium for stronger, healthier bones. But it doesn't take much time in the sun for most people to get the vitamin D they need, and unprotected exposure to the sun's ultraviolet rays can cause skin damage.

Most children rack up between 50% and 80% of their lifetime sun exposure before age 18, so it's important that parents teach their children how to enjoy fun in the sun safely. With the right precautions, you can greatly reduce your child's chance of developing skin cancer.