By Dinah Wisenbreg Brin, CNBC.com
On sunny days, Dr. Brad Merritt has watched on the sidelines of his son's sporting events from the shade of his umbrella. The 37-year-old dermatologist, who already has had basal cell skin cancer on his face, is determined to protect himself from the sun.
"Is there any such thing as a safe tan?" asked Merritt, assistant professor of dermatology at the University of North Carolina. "The answer is, `There is not.'"
Despite piles of research on the skin cancer risks of sun exposure and tanning beds, dermatologists and cancer groups struggle to persuade people to protect their skin from ultraviolet rays.
Encouraged by media images and tanning industry marketing showing tans as sexy and healthy, many people - especially teens and young adults - head to the beach, backyard or tanning bed to get that look, notwithstanding warnings and public service announcements about cancer, premature wrinkling and blotchy skin.
Skin cancer is now the most common form of cancer in the United States, with more than 3.5 million diagnoses each year in more than 2 million people, according to the Skin Cancer Foundation.
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The problem comes with human and financial costs - much like other pressing health problems in America, such as Alzheimer's and our aging population. Roughly one American dies of melanoma every hour, health advocates say. And skin cancer in the U.S. costs an estimated $1.7 billion to treat and $3.8 billion in lost productivity a year, according to the U.S. Centers for Disease Control and Prevention.
Meanwhile, the incidence of skin cancer appears to be increasing. Treatment of non-melanoma skin cancers in the United States rose by nearly 77 percent from 1992 to 2006, according to the Skin Cancer Foundation.
Skin melanomas rose by nearly 24 percent for men and more than 26 percent for women in the U.S. from 2004 to 2008, according to the CDC.
Diagnosis of melanoma, the deadliest form of skin cancer even though it accounts for less than 5 percent of all cases, has risen dramatically among young adults. It's the most common form of cancer among people ages 25 to 29 and the second-most common for those 15 to 29, the Skin Cancer Foundation says.
"Though we're trying harder than ever, there's a little bit of a deaf-ear effect," said Dr. David Bank, spokesman for the Skin Cancer Foundation and assistant clinical professor at Columbia University-Presbyterian Medical Center in New York.
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Despite the death rate, melanoma is "theoretically, 100 percent curable" if people would at least get annual skin checks and catch it early, he said.
Bank cited recent research from the Mayo Clinic showing that from 1970 to 2009, melanoma incidence increased eightfold among young Minnesota women ages 18 to 39 and fourfold among young men.
The increase may be linked in part to greater awareness and detection as many more people now visit dermatologists and more physicians in other specialties refer patients, Bank said.
"I think there's been a whole constellation of reasons why those numbers are there," and it will take more time to ferret out whether there's a greater prevalence of the disease itself and not just wider diagnosis, Bank said.
Over protests from the indoor tanning industry, health advocates in and out of government draw a link to sunbeds, pointing to studies indicating that ultraviolet radiation from indoor increases melanoma risk by 75 percent.
The World Health Organization has added UV radiation from tanning beds to its list of the most dangerous carcinogenic radiation, the National Council on Skin Cancer Prevention notes.
"Some in the public health community compare indoor tanning - a $5 billion a year industry -to the tobacco industry: both tobacco and tanning are associated with cancer and other health risks; both are sold as providing positive social benefits; and both get their customers when they are young and less concerned about the long-term health risks," the council says on its website.
Various other research points to risky tanning behavior among young adults.
A 2011 CDC report found that from 1999 to 2009, the percentage of white U.S. high school students who never or rarely wore sunscreen when outside on sunny days increased from 57.5 percent to 69.4 percent.
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The CDC, seeking a baseline measure of indoor tanning use before implementation of a 10 percent federal tax, looked at data from the 2009 national Youth Risk Behavior Survey. The CDC found that 15.6 percent of high school students had used indoor tanning devices over the previous year, and almost half of those students had used indoor tanning 10 or more times.
"Given the high prevalence of indoor tanning device use among US high school students and the associated risk of melanoma, strategies to reduce exposure must be examined," the CDC study said.
Another CDC study looking at indoor tanning among high school males found associations with, among other behaviors, use of steroids without a doctor's prescription and unhealthy weight control practices.
Understanding the relationship between indoor tanning and other appearance- and health-related behaviors would be helpful in designing interventions for skin cancer prevention, the CDC concluded.
"Frequent sunburns, suboptimal sunscreen use, and high rates of tanning bed use are commonplace even among the children of health professionals who are at risk for developing skin cancer themselves as a result of personal or family history," concluded a 2006 Boston University study published in the journal Pediatrics.
Dermatologists consider tanning beds to be more intense and dangerous than tanning in the sun, and note that users can become addicted.
UNC's Merritt said that indoor tanning has been shown to release endorphins. "It feels good and so people go back for more," he said. "People become addicted to tanning beds."
While the U.S. tanning salon industry, hit by the economic downturn, contracted by 1 percent a year from 2007 to 2012, it's expected to see 1.1-percent annual growth over the five years to 2016, according to IBISWorld.
Campaigns against tanning haven't fallen entirely on deaf ears, however.
IBISWorld projects that over the five years to 2016, the U.S. self-tanning product manufacturing industry - i.e., spray and lotions that give a tanned look - is projected to see 12.8-percent annual growth. The economic downturn didn't slow that industry, IBISWorld said.
Nevertheless, those using indoor ultraviolet tanning are 74 percent more likely to develop melanoma than those who've never tanned indoors, according to the Skin Cancer Foundation, which says that nearly 30 million people use indoor tanning in the U.S. annually, including 2.3 million teen-agers.
The Indoor Tanning Association, which has fought state legislation to ban teen use of tanning salons, took issue with the Mayo Clinic this year for linking the rise in melanoma incidence among young adults to sunbeds. The organization contends there's no consensus among researchers on the relationship between melanoma and ultraviolet exposure from the sun or tanning salons.
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State legislatures, though, have been trying to cool indoor tanning use among teens. Roughly 35 states have passed laws restricting indoor tanning for minors, although many allow it with parental consent or for older teens. Only California and Vermont have prohibited all minors from using indoor tanning centers.
Changing public opinion may be more effective than legislating change, said Merritt, who suggested that young people need a different mindset. Effective campaigns to prevent skin cancer may need to emphasize that skin is most beautiful and healthy in its natural, untanned state, he said.
Some state dermatology societies are working with schools on sun safety programs, and the government and cancer groups have developed programs as well. The American Academy of Dermatology has created public service announcements, including one, "Born," with just the sort of message that Merritt referenced. It's an anti-tanning ad featuring pretty, untanned babies, children and women.
See full coverage: Healthy Business 2012
By Dinah Wisenbreg Brin, CNBC.com