Feature Archive

Skin Cancer Danger: Not Just in Summer

Snow on the ground doesn't mean you don't have to worry about sun exposure. Sunburns -- and skin cancer -- can happen even in winter months.

By Dulce Zamora
WebMD Feature

Reviewed By Charlotte Grayson

I said goodbye to summer when I packed away my bikini for cold weather hibernation, only to fish it out weeks later for a trip to Australia, where the seasons are opposite what they are in the U.S. The fall and winter months here are seasons of spring and summer there.

Down under, I discovered a good number of people were wearing light long-sleeved shirts and hats at the beach -- not because they were shy of exposing their bodies, but because of a general awareness that the country has the highest skin cancer rate in the world.

One out of every two Aussies will develop non-melanoma skin cancer in their lifetime, accounting for about 80% of all new cancers diagnosed in the country each year, according to The Cancer Council Australia.

The alarming information was enough to motivate me to wear sunscreen during my outdoor ventures in Sydney. It turns out, however, that I also needed to be vigilant about protecting myself from too much ultraviolet (UV) exposure even when I got back home to the autumn leaves of New York. Experts say the danger of developing skin cancer can be just as significant in the U.S., even in the nippy seasons.

Skin cancer is the most common form of cancer in the U.S., making up more than half of all cancers here. More than 1 million Americans are diagnosed with the disease each year.

To help improve rates, American health officials are turning to some of the most successful sun protection campaigns produced in Australia. The effort, though, comes at a time when British researchers are questioning the effectiveness of sunscreen, long touted to help fight skin cancer.

There may be debate about sun block, but there is little disagreement about the importance of protecting oneself against too much UV light.

"The opportunity is there for people in the U.S. and Europe to learn from (Australia's) experience and to invest in prevention of skin cancer now," says Terry Slevin, director of education and research for the Cancer Foundation of Western Australia. "If not, (the Americans and Europeans) will pay for the lack of investment in the harvest of skin cancers that will be coming along the track in increasing numbers in 10, 15, and 20-year's time."

The Skinny of Vulnerability

Australia's experience with skin cancer does yield numerous lessons about risk factors for the ailment. In fact, some of these could apply to people in the U.S. and Europe, perhaps making more plausible a prediction of higher skin cancer rates in the future.

Skin cancer develops with cumulative overexposure to invisible UV radiation from the sun. When UV light penetrates the skin, it can damage skin cells and cause them to mutate over time. If these mutated cells aren't destroyed by the immune system, they could develop into skin cancer.

Here are some of the reasons why Australians are so vulnerable to the disease and how the same hazards could affect Americans and Europeans:

'Who's the fairest of them all?' Most Australians migrated from Northern European territories. "We're basically a pale-skin population living in a dark-skinned people's land," Slevin explains. "We've been here for only a little over 200 years and our skin hasn't adapted to the ultraviolet radiation that we're exposed to."

Slevin says the growth of international travel by Americans and Europeans to warm, sunny lands during the fall and winter months has also increased their amount of UV exposure.

Skin is in. In Australia, the U.S., and Europe, exposure to the sun has apparently increased with a strong cultural desire for light-skinned people to get a tan and with a change in dress since the early 20th century.

"People used to shun the sun with their hats and parasols," says Martin Weinstock, MD, PhD, chairman of the skin cancer advisory group for the American Cancer Society. Now, showing bare midriffs and more leg, even outside the beach, is acceptable in many parts of the western world.

Fun in the sun. If it's sunny out, people in Australia tend to go to the beach and play, says Kendra Sundquist, PhD, spokeswoman for The Cancer Council New South Wales. The same could certainly be said of people in other parts of the globe. With a host of outdoor activities from surfing to in-line skating to gardening, there are plenty of reasons for people to venture outside on nice days.

Unfortunately for people down under, Australia is situated in an area of the planet that is closest to the sun in summertime, which means more intense UV exposure.

Exposure to the sun's harmful rays isn't limited to one area of the world, however. Each country's UV levels vary in different seasons, depending on their geography. And in a large place like the United States, the variables are even greater. The UV levels in Florida, for example, are different from those in Maine, explains Weinstock.

In addition, UV radiation doesn't necessarily depend on temperature or season, as more people get sunburned in Australia in the cooler days of fall and spring, says Craig Sinclair, chairman of The Cancer Council Australia's skin cancer committee. It is reportedly likely that UV light can cause more damage at this time because people don't normally think of sun protection during the fall and winter.

Again, this is not purely an Aussie phenomenon. Sinclair notes that worldwide, UV radiation goes up 3% for every 400 meters (about 1,312 feet) of altitude. Plus, UV light is reflected from snow (about 80%), and from clouds on overcast days. This could mean a double dose of exposure.

The heat is on. There are reports that the infamous hole in the ozone layer may contribute 2%-3% to Australia's skin cancer risk, although there is no direct evidence, says Slevin. Nonetheless, a recent World Meteorological Organization report that the ozone hole is growing faster this year than in previous years, and that it is as large as the all-time record of 28 million square kilometers (about 17.4 million square miles) set back in September 2000, can't be good news for Australia and other parts of the world.

The ozone layer usually acts as a natural barrier against the sun's damaging rays, and if the thinning of this protective substance isn't controlled, there is tremendous potential for the U.S. to be affected, says Weinstock. Right now, he says, the problem is probably having more of an impact on polar areas such as Southern Australia.

Preventing Skin Cancer

To curb its spiraling rates of skin cancer, Australia has aggressively promoted several sun protection campaigns in the past two decades. The most popular is the Slip! Slop! Slap! program, in which people are encouraged to slip on a shirt, slop on sunscreen, and slap on a hat before going out in the sun.

The Sunsmart program also calls for people to:

  • Stay in the shade during midday hours (usually around 11 a.m. to 4 p.m.), the prime time for UV exposure.
  • Dress in clothing that covers arms, legs, and neck. In Australia, many garments have UV ratings on the labels, which indicate how well they protect skin.
  • Don a broad-brimmed hat.
  • Put on sunglasses that block out 95%-100% of UV rays.
  • Wear sunscreen that has at least a sun protection factor (SPF) of 30 or more. It must be applied at least 20 minutes before going outside in order to give it time to bond with the skin.

The Australian initiative has been so successful in changing attitudes about sun protection that countries such as the U.S., U.K., and New Zealand have borrowed it to beef up their own skin cancer prevention drives.

A recent study in the U.K., however, appears to throw a wrench into this sun protection campaign and many others that advocate the use of sun block. Researchers from the nonprofit charity group, the Restoration of Appearance and Function Trust (RAFT), found that sunscreen may be less effective than previously thought in protecting against hazardous UV light.

Additionally, scientists say the use of sunscreen gives people the impression they could stay out longer in the sun, thereby compounding the problem.

Nonetheless, sunscreen still appears to have big support as an important albeit imperfect tool for skin cancer prevention.

"Sunscreen should be used to complement other sensible sun protection measures, including use of shade, protective clothing, hats, and sunglasses," says Sinclair, in an official response to the RAFT research, released by The Cancer Council Australia.

Weinstock of the American Cancer Society says there's no question that sunscreen is effective in protecting the skin from harmful rays because studies have been done to prove it.

Spring in Sydney, Autumn in New York

No one is at zero risk for developing skin cancer, whether you are bushwalking outside Sydney, skiing in the Rockies, trekking through the man-made jungle of New York, or playing rugby in London.

A person's overall risk, says Weinstock, depends upon many factors, including one's location on the planet, the elevation of the place, the time of day of exposure, length of time in the sun, susceptibility to disease, and a host of other personal circumstances.

What is important is to be aware of warning signs of skin cancer because early detection is critical to survival.

"People need to look at their skin carefully on a regular basis, and if they see a spot on their skin that is changing in size, shape, or color, they need to bring it to the attention of their doctor," says Weinstock.

Originally published Dec. 29, 2003.

Medically updated Oct. 27, 2004.




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