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We live in a world of dangerous contradictions: Old dental fillings cause mercury poisoning.
Unleaded gasoline ingredients clean the air but poison our ground water supply. And now here’s
one that’ll really make your skin crawl if you like to spend your summer running, riding, and
playing outdoors: Sunblocks help cause skin cancer.
Last year, the FDA ruled that sunscreens can no longer be labeled “sunblocks” because
they are incapable of absolute protection. In fact, 10 separate studies presented at the
American Association for the Advancement of Science showed no evidence that sunscreens prevent skin
cancer. It appears that most sunscreens only stop one type of ultraviolet rays, UVB, the cause
of the telltale sunburn redness—but not its longer-wavelength sibling, UVA, which penetrates
even deeper into the epidermis. UVA not only increases cancer risk, but also is directly
responsible for skin wrinkling and leathering.
The bottom line
That led to a universally accepted conclusion by one study leader, Marianne Berwick, Ph.D., of New
York’s Memorial Sloan-Kettering Cancer Center: The use of sunscreens unwittingly helps
cause cancer.
Sunscreens, she said, fool us into staying outside longer. As your skin is being destroyed, its
coat of sunscreen makes it appear pristinely pale—so you stay out in the sun longer and get
damaged even more.
So what’s an outdoor athlete to do? Toss the sunscreen and pedal your indoor trainer
all summer? Run while covered from head to toe, like Afghan women under the Taliban?
First, the scary facts
The incidence of skin cancer is skyrocketing. One of every two Americans could be afflicted by age
65, studies predict. This year alone, anywhere from 600,000 to one million Americans will be
diagnosed with basal cell or squamous cell carcinoma, the most curable skin cancers. Melanoma, the
deadliest form of skin cancer, has risen 5 percent a year in the United States since 1950, now
striking 44,000 of us annually and killing 7,300.
The main reason for the rise is something you hear about in the news every day: A pronounced
thinning of the ozone layer, the atmospheric layer that protects us from deadly ultraviolet rays.
According to the EPA, it will be thinning an estimated 8 percent per decade from now on. This
leads us to our earlier question: What to do?
Smarter sunscreens, safer habits
“Remember two things,” says Dr. Henry W. Lim, the Chairman of the dermatology department
at Detroit’s Henry Ford Hospital and a member of the Photobiology Committee of the Skin Cancer
Foundation. “First, to read labels—more and more new ’wide-spectrum’ sunscreens
with anti-UVA chemicals are coming out now. Secondly, sunscreen is just part of an entire sun
protection system.”
Get a super-screen. New broad-spectrum sunscreens block all rays, UVA and UVB, with
chemicals such as titanium dioxide, Parsol 1789 (avobenzone), and Z-cote (a transparent form of
zinc oxide, the original, messy UV blocker you see on lifeguard’s noses). Eight-time Ironman
Triathlon winner Paula Newby-Fraser, who had two chunks of pre-cancerous basal cells surgically
removed from her shoulders in 1997, now won’t go out without a thick coat of Banana Boat SPF
50, which has the words “UVA and UVB protection” printed on the label plus a Skin Cancer
Foundation (SCF) Seal of Recommendation.
Lay it on thick. Reapply often. A suncreen’s effectiveness is reduced because people
often use about one-quarter the amount they should—and miss exposed areas like ears, scalp,
neck, hands, and lips. (As a guide, use a teaspoon’s-worth on your face and several times
that for your body.) Also, since sunscreen’s potency significantly decreases over time, and it
rubs, towels, sweats, melts, and washes off easily, reapply it sooner than the SPF rating
indicates.
Use SPF 15, minimum. The SCF recommends an SPF of at least 15 for everyone, regardless of
skin color. SPF refers solely to skin protection against UVB rays. If you’re fair-skinned,
or at a high altitude, on the beach, or near the equator, consider an SPF from 30 to 50.
Here’s the math: If you’re pale, with skin that normally takes 7 minutes to burn, SPF 15
will protect it for 1 hour, 45 minutes (7 x 15 = 105 minutes).
Consider, however, that sunscreen use is just the tip of an entire sun-protection system that
includes changing your workout times and changing your clothing. Start your rides and runs at dawn
or after 4 p.m. to avoid the strong UV rays of the midday sun. And cover up with a broad-brimmed
hat, a helmet visor and a dark-colored, long-sleeved jersey. Don’t wear a white shirt,
which lets in lots of UV rays when it’s wet and sweaty. Newby-Fraser says she’s given up
tank tops forever.
Find shelter
In New Zealand, which sits directly under the famous hole in the ozone layer and has double the
skin cancer rates of the U.S., children are sent home from school if aren’t wearing sunblock
and an expedition-style hat (which shades the back of the neck as well as the face).
And on Auckland beaches, 1920s-style “full-coverage” bathing suits are coming back in
style. In fact, it might be a good idea to forget the beaches altogether. Not only is the
minimal attire bad, but reflection off water and sand instantly increases UV exposure by 50
percent.
Finally, know the enemy and act fast. Melanoma, a cancer that originates in the melanocytes, the
skin’s melanin-producing cells, appears first as large or jagged-edged moles. Scrutinize
arms, legs, neck and head, especially the nose, ears and lower lip; the SCF says 80 percent of skin
cancer lesions occur there. If they’re amorphous in shape, arose quickly, or itch, get to
a doctor fast. It could save your life. Around 95 percent of victims survive the removal of shallow
skin cancer cells (less than a depth of .75 mm ), while only half live when the cancer is more than
4 mm deep.
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