Experts fear salons are no safer than sun, but level of risk is unclear
10:09 PM CDT on Sunday, July 3, 2005
The tan you buy may be no safer than the one that comes for free.
Once hoped to offer a better way to brown, tanning salons now take as
much heat from medical experts as the sun. The World Health
Organization recently stated that artificial tanning "may provide the
ideal setting for the development of malignant skin cancer" because
users get periodic bursts of intense radiation. In addition, people in
tanning beds often place their whole bodies under the ultraviolet
light, leaving about twice the surface area exposed to direct rays.
Some doctors even suspect that tanning bed popularity may be one reason
why younger people appear to be getting skin cancer with increasing
frequency. However, even in issuing its opinion, the
health organization acknowledged that research so far has not provided
consistent results. "There are different arguments as to
how much risk there actually is," said Dr. Martin Weinstock of Brown
University. This month, Dr. Weinstock attended an international
gathering of experts the World Health Organization invited to France to
evaluate artificial tanning risks.
One of the difficulties in studying tanning device hazards, scientists
say, is that cancer patients who have spent time in tanning beds have
also tended to love the sun, making it difficult to tease out whether
their risk came from natural or artificial light. Cancer usually
smolders for decades before it flares up on the skin, so most studies
must rely on asking patients about sunning habits they had years
before. And because cancers like melanoma are deadly but not among the
most common malignancies, the studies up to now have been small.
One thing has not been in dispute. That lovely bronze is a response to
radiation. "UV light clearly causes DNA damage," said Dr. Patrick Hwu,
the chairman of melanoma medical oncology at the University of
Texas-M.D. Anderson Cancer Center in Houston. If indoor tanning is
doing its job by UV light, he said, "I think it's not safe." But how unsafe is it?
To try to answer that question, researchers from the University of
British Columbia recently pooled data from more than a dozen studies
looking at the melanoma risk from artificial tanning. In a report
published in March in the journal Cancer Epidemiology Biomarkers and Prevention,
the Canadian scientists found that, overall, tanning bed use appeared
to almost double the risk of melanoma. That would mean an American
man's lifetime risk of melanoma, now about 1 in 50, would rise to about
2 in 50 with regular tanning bed use. However, "it's not
the kind of thing where you're going to have one message for the entire
population," said Richard Gallagher of the British Columbia Cancer
Agency, who led the research. Skin cancer is a much higher danger among
the fair-skinned – the very people most likely to use a tanning bed.
A person's risk of melanoma has been linked to the number of burns they
have experienced in their youth. So, in theory, a tanning bed – if it
keeps a person from burning – might appear to lower melanoma risk. Dr.
Weinstock points out, however, that the burn itself may not be the
harming factor. The sunburn could just be a warning signal that the
person's skin is particularly sensitive to radiation. The
two other types of skin cancer, basal and squamous cell carcinoma, are
more often associated with a person's total exposure to the sun.
Research has suggested artificial tanning also increases the risk of
those cancers. For example, one study from Dr. Weinstock and his
colleagues of cancer patients in New Hampshire suggested that tanning
devices more than doubled the risk of squamous cell carcinoma.
"The key question is," Dr. Weinstock said, "why do people go and get
this exposure voluntarily? You can get your tan in a bottle if you
really need a tan." People seem to tolerate carcinogens
when they are enjoyable and addictive, and some people who frequent
tanning beds may feel a similar, though weaker, draw. Studies have
suggested that ultraviolet light stimulates the release of endorphins,
the body's own opiatelike compounds. Scientists from Wake Forest
University School of Medicine in North Carolina have found that
frequent tanners can distinguish a tanning bed with actual UV light
from a sham bed simply by the way it makes them feel. "UV light has a physiologic effect that drives people's behavior," said Wake Forest's Dr. Steven Feldman. Yet despite the fact that doctors may be battling fashion and physiology, they remain resolute.
"We know we have a lot of work to do," said Dr. Clay Cockerell, a
Dallas dermatologist who is also president of the American Academy of
Dermatology. "You've got to make it cool to be safe. That's not easy to
do." A tan offers immediate reward, but cancer is a
distant threat. "It usually takes about 20 years or so of skin damage
to get skin cancer," Dr. Cockerell said. But by the time patients get
to his office, he said, "they do usually regret it." E-mail lbeil@dallasnews.com