Back when the Beach Boys were first surfing radio airwaves, stores sold only one type of sunscreen: the greasy white goop that reeked of chemical coconut. It wasn't pleasant, but it wasn't complicated either.
Since then, the tide has turned. As research sheds new light on the dangers of sun exposure -- and 2 million Americans continue to develop skin cancer every year -- sunscreen manufacturers have raced to introduce an ever-growing array of protective products. Now consumers are left puzzling the intricacies of the ultraviolet bandwidth, sorting through enough chemicals to fill a periodic table, and choosing among sunscreens in forms ranging from sprays to wipes.
Are you at risk for a solar slipup? Read on as leading dermatologists dispel the top misconceptions.
At some point over the years, you've probably heard that 80 percent of a person's sun exposure occurs during childhood. That might leave you wondering whether there's any point in protecting skin now. Wonder no more -- that stat has been soundly debunked.
A study conducted by researchers from the FDA and other institutions found that less than a quarter of all UV exposure happens during childhood and adolescence. (The group that gets the most sun? Men over 40, according to The Skin Cancer Foundation.) And considering that American life expectancy over age 50 has risen every year for the past quarter century, safeguarding skin is more important than ever. "It's wise to protect yourself no matter how old you are," says Charles Crutchfield III, M.D., a dermatologist at the University of Minnesota. "Every day offers a chance to reduce your skin cancer risk."
You already know to check a sunscreen's SPF to see how well it blocks UVB radiation, the type that causes visible burns. It takes a little more detective work to find out if the product shields against UVA1 and UVA2, two cancercausing solar wavelengths that penetrate skin more deeply.
Sunscreens labeled "broad spectrum" might not cover all your bases, says Joshua Zeichner, M.D., a dermatologist at New York's Mount Sinai Medical Center and a spokesperson for the Skin Cancer Foundation. Many broad-spectrum formulas shield against only one type of UVA, and a few block neither.
To find a sunscreen that really delivers, start by choosing a product with an SPF of at least 30, then look for a combo of proven UVA blockers in the ingredient list. Those that protect against UVA1 include zinc oxide (also a UVA2 blocker) and avobenzone, which is also marketed under the names Helioplex and AvoTriplex. In addition to zinc oxide, UVA2 blockers include oxybenzone, titanium dioxide, and ecamsule (trade name Mexoryl). Two brands that fit the bill: Neutrogena Ultra Sheer Dry-Touch Sunblock SPF 45, and Aveeno Natural Protection Mineral Block Sunscreen Lotion SPF 30, both available at drugstores.
Granted, a uniform layer of super-thick clouds can keep some solar rays from striking Earth. But leaving skin unprotected is risky even when sunshine is scarce, Dr. Zeichner says. In some cases, UV rays can barrel right through. If clouds are clustered and dense, UV radiation can reflect off their surfaces and bounce to ground level. As if that weren't enough, UV intensity varies with fluctuations in atmospheric ozone cover. Luckily, you don't need a weather balloon to make sense of it all.
Simply check your local UV Index, which weighs these variables to predict the midday intensity of ultraviolet rays on a scale of 1 to 11. (Anything above a 5 means the risk of sun damage is high.)
Remember that on any given day, the sun's rays are strongest between 10 a.m. and 2 p.m.
The definition of "waterproof" is self-evident -- unless you're talking in sunscreen parlance.
Technically, this term means the product is formulated to withstand up to 1 hour and 20 minutes of water immersion. (Meanwhile, sunscreens labeled "water-resistant" can endure a 40-minute dunk.)
To keep consumers from developing a false sense of security, the new FDA rules would prohibit the use of "waterproof" and "all-day protection" on sunscreen labels, says Joshua Zeichner, M.D., a dermatologist at New York's Mount Sinai Medical Center and a spokesperson for the Skin Cancer Foundation.
For now, no matter what the label on your favorite brand implies, reapply sunscreen every hour or so when you're swimming. Also consider that waterproof doesn't mean sandproof, towelproof, or surfproof. Give yourself a fresh coat any time your skin is subject to abrasive forces.
Paying a little more for a sunscreen with triple-digit SPF seems like money well spent. After all, doesn't a bigger number mean you can safely spend more time in the sun?
Not exactly. SPF is part of a complex formula based on the percentage of UVB radiation that's deflected from skin -- a formula that yields diminishing returns as SPF climbs. "SPF 30 protects you from 97 percent of UVB light; SPF 50 is only slightly better, shielding you from 98 percent," Zeichner says. In other words, no 6-hour sun naps allowed.
And bear in mind that a sunscreen's protective power is strongest when it's fairly fresh on your skin. Chemical UV blockers (such as avobenzone and oxybenzone) break down as they absorb rays, and any sunscreen becomes less effective as sweat, water, and friction wear it away. Save your money and stick to a product in the 30–50 SPF range, reapplying at least every two hours depending on your activities.
Vitamin D is essential to optimal health -- this multitasking nutrient promotes calcium absorption, boosts immunity, and keeps inflammation in check.
Conveniently, bare skin makes vitamin D in response to UV exposure. Why slather on sunscreen and mess with a good thing? Because the danger of getting skin cancer is bigger than the risk of developing a D shortfall from using sunscreen, say experts from the American Academy of Dermatology.
In lieu of unprotected sunning, the academy recommends that adults get 600 IU of vitamin D per day through supplements or dietary sources such as sockeye salmon and fortified foods like milk, orange juice, and cereal. Not that sunscreen shuts down D production entirely anyway.
"Sunscreens block most -- but not all -- UV light," Dr. Joshua Zeichner adds. "The small percentage of rays that do hit your skin help the body maintain vitamin D levels, as well."
Spray-on sunscreens are great for covering large areas of skin quickly. But the instructions on many brands are vague, directing you to apply "generously" or "evenly." This makes it tough to tell when you've spritzed on enough
Eliminate the guesswork by following the Sweet 16 rule, advises Dr. Charles Crutchfield. "You need at least 16 pumps -- or one-second sprays -- to cover the whole body," he says. (You might need one or two more, depending on your size.)
And while many brands tout their formulas as being "no rub," you might want to lightly pat damp skin anyway. "This eliminates the tiny spaces between droplets that can leave your skin vulnerable," says Clay Cockerell, M.D., a dermatologist at the University of Texas-Southwestern Medical Center.
Most mornings, you're careful to apply a moisturizer or foundation with sunscreen built right in. Smart move. Just note that if you're planning to be outside for more than 30 minutes or so, you need to dial up your defense plan.
Women tend to dab on cosmetics lightly, often skipping their T-zones and peripheral spots such as their earlobes and hairline. That leaves a lot of naked skin above the neck. In addition, cosmetics generally aren't formulated to withstand much sweating or water exposure, making them a no-no for warm-weather workouts. "Switch to a dedicated sunscreen and apply it liberally—you need at least a teaspoon for your face," Dr. Joshua Zeichner says.
Depending on their active ingredients, sunscreens remain stable for 1–3 years.
So before you put last summer's half-used bottle back into rotation, look for an expiration date and toss the product if it's past its prime. (Ditto for expired bottles with an unbroken seal.) No date? If you purchased the sunscreen more than 12 months ago, discard it just to be safe, Dr. Zeichner says—especially since there's no telling how long the product sat in the store before you bought it.
One tip for this year: If you buy a sunscreen containing oxybenzone, avobenzone, or ecamsule, be sure to store it away from direct sun when you're outdoors (a beach cooler makes an ideal spot). These chemicals become inactivated as they absorb light and heat, which can happen even if the container is opaque.
Sunscreens come in many forms. All are effective when applied properly. Which is best for you? It depends on the situation.
You've packed the trunk and filled the fuel tank, but don't hit the highway without safeguarding your skin. "Windows in cars block UVB rays but allow in UVA rays, which penetrate deeper into the skin and are responsible for many skin cancers," says dermatologist Joshua Zeichner.
That explains why one recent study at St. Louis University in Missouri found a direct correlation between frequent driving and skin cancer on the left side of the body. Whether you're driving or acting as copilot on your summer travels, be sure to put on sunscreen 20–30 minutes before you buckle up.