Sun and D, 1

"It all goes back to my childhood freckles. The grown-ups told me they were cute, and I believed them. And when they kept sprouting, I didn't mind. I figured I was getting cuter.
Like millions of middle-aged Americans, I spent youthful summers basted with baby oil, hoping the Midwestern sun would bake me into a California girl. My friends and I envied the kids with spring-break tans. We didn't give a thought to cancer.
I know better now. I wear sunscreen-the kind that includes fake bronzer-along with an SPF of at least 15. I check my skin for changes and visit the dermatologist annually. But even so, sitting in the sun with a book is still my idea of heaven. That's my idea of a vacation, too.

Skin types at the fair end of the spectrum are more susceptible to the burning rays of the sun -- and to a higher risk for cancers and premature aging of the skin. But a little sun exposure also releases endorphins and gives us needed vitamin D. WSJ's Melinda Beck and Laura Landro debate how good or bad the sun is for you on the News Hub.
The sun makes me feel good. In fact, ultraviolet (UV) rays stimulate the production of endorphins, the feel-good brain chemical, like exercise does. And my vitamin D levels are great, thanks to the sun's rays, so I figure I'm lowering my risk for a wide range of diseases.
But these days, sitting in the sun makes me feel guilty as well. A health columnist with a tan? Shameful.
Both the Skin Cancer Foundation and the American Academy of Dermatology maintain there's no such thing as a safe tan. And they keep raising the alarm levels. Some equate the urge to tan (or "tanorexia") with addictive behaviors like drug and alcohol abuse.
Most dermatologists advise never to step outside without sunscreen and they say it's not enough just to guard against UVB rays, the kind that cause burns. It's the longer, less intense UVA rays that accelerate aging-and those even penetrate cloud and glass windows. We also need specially made protective clothing.

Is all this protection really necessary, even for skin types like mine that tan easily? I posed some questions to dermatologists and other experts at a sun-care symposium, sponsored by the Coppertone Solar Research Center, this month. Admittedly, I was hoping someone would say that my tanning habit is OK. But I kept getting shot down.
The sun has been shining on us since life began. When did it become the enemy?
Skin cancer is rising mainly because we're exposing more of our bodies to the sun than ever before, these experts said. It's only been in the past 50 years or so that people equated a tan with health and wealth. In centuries past, the upper classes stayed pale; only laborers, cowboys and farmers sported tans, and they didn't lay out at noon in bikinis.
What Happens to Your Skin
The sun's ultraviolet rays are classified in three categories, based on their wavelength from the sun to the earth. UVA and UVB rays have harmful effects on the skin, while UVC rays do not reach the earth's surface. See chart
We're also living longer than ever, and UV damage is cumulative, so 50-, 60- and 70-year-olds are getting skin cancer based on decades of exposure.
And it's not just the sun that's causing problems, they said. Tanning parlors emit UVA rays far more intensely. "Not a month goes by when I don't see someone in their 20s with skin cancer," said David Leffell, a professor of dermatology at Yale School of Medicine. "Invariably they've been to tanning parlors and they are consumed by guilt."
Doesn't a tan provide some protection?
You'd think I had suggested setting myself on fire for fun. The assembled experts insisted that a tan is really a distress signal that UV rays are damaging the skin's DNA; the body sends melanin, its naturally occurring pigment, to the skin's upper layer to block UV rays from penetrating deeper. Tanning does provide some protection-the equivalent of an SPF 2 or 3, said Steven Q. Wang, director of dermatology at Memorial Sloan-Kettering Cancer Center in Basking Ridge, N.J. "But you have to pay for it with your DNA."
He and others also pointed out that sun exposure hastens the aging process, by damaging deeper collagen fibers and creating sagging and wrinkles. "That message seems to be more powerful than the skin cancer message," Dr. Wang noted. After all, there's a 100% risk of aging.
More
A Shade-Seeker Finds Ways To Block Rays How to Check for Melanoma as Risk Rises What about the benefits of sun exposure-like vitamin D and endorphins?
In his new book, "The Vitamin D Solution," Michael Holick argues that "sensible sun exposure" can prevent many more deaths from breast, colon, prostate and other cancers than it will risk from skin cancer. (The exact amount differs by skin type, latitude and time of year; it's 10 to 30 minutes three times a week, without sunscreen for Caucasians in much of the U.S. in the summer.) He also blames the widespread vitamin D deficiency on what he calls the rising culture of "sunphobia." Because of views like that, he chose to resign from Boston University Medical School's department for dermatology in 2004, though he remains a professor of medicine, physiology and biophysics.
The dermatologists said there are still many unknowns about vitamin D, such as how much people really need and whether it really protects against cancer and other diseases, to make such tradeoffs. Besides, they said, vitamin D is readily available from supplements without risking skin cancer. So far, however, there's no pill to replicate the mood-enhancing effects of the sun.
Isn't the cancer risk different for people with different skin tones or different parts of the world?
"Absolutely," said Dr. Leffell, who noted that someday personalized medicine may be able to predict exactly who can bask in the sun safely. In the meantime, experts are left with fairly broad categories of recommendations.
The people at highest risk for skin cancer are those who have fair complexions, freckles, red or blond hair and who always burn instead of tanning. They are Types 1 and 2 on what's known as the Fitzpatrick scale, developed in 1975 by Harvard dermatologist Thomas Fitzpatrick. They should wear SPF 30 or more and seek shade anytime they're in the sun, according to the Skin Cancer Foundation. People with Types 5 and 6-with naturally brown or black skin-are at much lower risk, even though they can get melanoma. People with Type 3 or 4, like me, as well as the 5 and 6's should wear SPF 15 outside and seek the shade between 10 a.m. and 4 p.m.
Skin type is a much bigger risk factor for cancer than latitude, which explains why skin cancer rates are highest among fair-haired people in places like Australia, New Zealand, North America and northern Europe, than in areas near the equator, even though the sun is stronger. Dermatologists say that fair-haired people need to be especially cautious when they vacation in sun-drenched places, or on ski slopes, with high altitudes and reflected sun on snow.
The Skin Cancer Foundation has also modified its overall public-health message in recent years from "Avoid the Sun" to "Seek the Shade." What's the difference? "We're saying go to the beach and sit under an umbrella. Enjoy all your outdoor activities but be protected. That's a wildly different message than stay inside and watch TV," says a spokeswoman.
"I think most of my colleagues would say, 'Enjoy the sun in moderation,' " says Dr. Wang. "That does not mean it's a good idea to lay half-naked on the beach for five hours. And you need to be extra cautious if you are fair-skinned."
Personally, I'm going to mull all this over this summer, sitting in the sun, but I'll try to make it before 10 or after 4.
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