WEDNESDAY, July 3, 2002 (HealthDayNews) -- You've heard the mantra a million times: Wear sunscreen and preserve your skin.
However, some researchers have questioned whether sunscreen really protects against the deadliest forms of skin cancer.
Now, in the latest twist in the debate, a team of analysts offers some good news -- slathering on the sun block doesn't appear to lull people into a false sense of security and lead to sun overexposure and potential health problems.
"Our data shows there is no risk from using sunscreen, and it implies it probably does what it's supposed to do. The most prudent thing to do is to use it," says study co-author Dr. Michael Huncharek, a radiation oncologist with the Marshfield Clinic Cancer Center in Wisconsin.
Skin cancer will strike more than 1 million people in the United States this year. About 54,000 will get melanoma, the most serious of the three types of skin cancer and the fastest-rising form of cancer in this country, according to the American Cancer Society.
Some experts have argued that sunscreens may actually do more harm than good when it comes to melanoma. One argument suggests people use sunscreen incorrectly -- mainly by putting on too little -- and stay in the sun longer than they would have otherwise.
"It's kind of like no-fat brownies. You're eating them and gaining weight because you're getting rid of the fat but not the calories," says Dr. Kenneth Ellner, chief of dermatology at Southeast Permanente Medical Group in Atlanta.
Also, there is debate over protection from harmful ultraviolet rays. Until recently, many sunscreens provided significant protection only against ultraviolet-B radiation (UVB), and not against ultraviolet-A radiation (UVA), Ellner says.
While researchers know sunscreens with UVB protection work against largely curable skin cancers known as basal cell and squamous cell carcinomas, melanomas are a different matter, he says. UVA may play a major role in their development.
In his analysis, Huncharek reviewed 11 studies that looked at links between sunscreens and melanoma cases. The findings appear in the July issue of the American Journal of Public Health.
By using a statistical technique known as "meta-analysis," Huncharek found no suggestion that people who use sunscreens are more likely to develop melanoma.
Ellner says researchers have much more to learn about melanoma. Genetics appear to play a role, and the immune system may also affect whether someone gets the cancer, he says.
Oddly, he says, "incidence of melanoma is less in roofers and people who work in the sun than in occasional sun worshipers."
Both Huncharek and Ellner agree that people who go outside should slather on sunscreen. It's important to use it liberally and reapply it frequently, Huncharek says.
Ellner suggests the use of sunscreens that include these ingredients: zinc oxide, titanium dioxide and avobenzone (also known as Parsol 1789 or 1789). Over the past few years, more sunscreens have begun including those ingredients, he says.
Melanoma is treatable in its early stages, but becomes deadly once it spreads to other parts of the body, Huncharek says.
What To Do
Learn more about protecting your skin from the Skin Cancer Foundation. howstuffworks.com site explains how sunburns -- and suntans -- occur.
