The dark side of the sun and its effects on skin

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KINGSTON, R.I. – July 6, 2010 – Summertime is full of fun, but as we all know, too much sun can cast a shadow on the good times.

The sun’s ultraviolet (UV) rays are the principal cause of skin cancer, a disease that now accounts for more than a million — or about half — of all new cases of cancer diagnosed each year.
But it’s so simple, right, to avoid skin cancer?

Yes, according to Joseph Rossi, the University of Rhode Island’s sun exposure and skin cancer expert, protection is the sole remedy. But the biggest factor affecting the increased number of skin cancer cases each year all boils down to behavior.

“Our research has focused on the behavioral aspects of skin cancer prevention for about 20 years,” said Rossi who is the director of research at the University’s Cancer Prevention Research Center and professor and director of the behavioral science PhD program in the Department of Psychology. “We’ve shown that people can modify their behavior to adopt healthier and safer sun practices and still enjoy themselves in the sun. Yet like most health behaviors, change is not easy and it takes consistent effort and commitment.”

Compared to other risky health behaviors like smoking and being sedentary, Rossi says many people do not consider sun exposure in the same category.

“But Melanoma, the most serious form of skin cancer, is the fastest-increasing cancer in those aged 25-29, who are also less inclined to take protective measures,” explained Rossi.

He says that teens generally think of skin cancer as a disease for the elderly, and that looking “decrepit” is only to be expected when you reach the “ripe old age of 30” or so. Teens don’t feel any urgency at all about the risks of unprotected sun exposure whether on the beach, in tanning salons or sunbeds.

Go Broader, not Higher

Rossi said there are three basic protective steps:
1) As much as possible, avoid going outside during the mid-day hours, from 10 a.m. to 4 p.m., when the sun is at its highest;
2) Can’t avoid going out in the mid-day? Then dress for it! Wear longer sleeved shirts, long pants, hats with a wide brim, and sunglasses (remember that eyes are at risk too!);
3) For uncovered areas of the body, wear a waterproof, broad spectrum sunscreen with a sun protection factor (SPF) of at least 15.

Rossi explained that the higher the SPF number, the greater the protection, but beyond an SPF of 15 or maybe 30, increasing SPF doesn’t provide much additional protection.

“Certainly SPF’s of 50 or 100 are not 3-6 times “better” than SPF 15 in any sense, and would not generally be worth paying more for. But you should get a sunscreen that is labeled ‘broad spectrum’ since it will protect against both UV-A and UV-B rays, both of which have been found to be important in causing skin cancer. A sunscreen that is waterproof for protection while in the water or from sweat is worthwhile,” Rossi said.

Sunning “Indoors”

The increased numbers of tanning salons and artificial tanning devices, especially in areas near colleges and universities has fueled myths and misinformation about skin cancer. Before vacations or ‘spring break’ trips, students may buy into the idea of “building up” a “protective” tan using a “sun lamp” or tanning bed so that they can then go to the tropics and safely lie out in the sun.

“This is simply wrong, and likely to result in a painful sunburn as well! It’s true that tanning beds, when safely regulated, emit only UV-A radiation, whereas the sun emits both UV-A and UV-B, but both forms of UV rays are associated with increases in skin cancer,” Rossi said.

Aging Skin

Beyond skin cancer itself, Rossi says a less well-known risk from the sun is called “photoaging”. The sun’s UV rays cause the skin to age faster than it normally would, resulting in wrinkles, loose skin, discolored skin such as freckles and “sun” or “liver” spots.

“Generally most, if not all, of what we usually consider “normal” aspects of aging skin are in fact caused by unprotected exposure to the sun. You can easily see this yourself by simply comparing some areas of your own skin that are often exposed to the sun with those that are usually not exposed, like the top of your forearm compared to the bottom of your forearm. The unexposed areas will be softer and smoother. This is no accident!

“The bottom line is, the increase in skin cancer cases is not related to how hot it is, to climate in general, or to the often mentioned “ozone hole.” It’s all about behavior – getting folks to stay inside at mid-day, keep their clothes on and/or slather on sunscreen for safety!”