By Brenda Goodman, MA
WebMD Health News
Reviewed by Brunilda Nazario, MD
Latest Skin News
May 28, 2013 -- Summer is nearly here, and that means it's time to stock up on sunscreen. But as anyone who's slathered or sprayed only to wind up with a stinging sunburn can tell you, not all sun protection is created equal.
"In the past, you almost had to be an organic chemist to know what to look for on sunscreen labels, whether it was protecting you or not," says Darrell Rigel, MD. He is clinical professor of dermatology at New York University Medical Center.
New FDA rules for sunscreen labels are going to make it a whole lot easier for people to compare products when they shop for sunscreen. Here's what to look for:
Broad spectrum coverage. Before the new rules, the term "broad spectrum" had no meaning. Now, the FDA allows sunscreens to use the term only if they pass a certain test for blocking UVB and UVA rays.
SPF above 30. SPF, or Sun Protection Factor, refers to the length of time a person can stay out in the sun with the sunscreen on before they'll burn. In theory, the higher the number, the longer your protection lasts.
But SPFs come with a big catch. Sunscreens are tested for SPFs at a certain thickness on the skin, says Rigel, and people rarely use that much.
"The reality is that if you're using a 50 and you're applying half the normal rated amount, you're getting between a 12 1/2 and a 25 at actual use," he says. Higher SPFs offer better insurance against sunburn, in case you don't put enough on.
Water resistance. Your old sunscreen might have claimed to be "waterproof" or "sweat proof." Those terms are no longer allowed under the new FDA rules because they are misleading, Rigel says. Instead, bottles will now say whether a sunscreen is water resistant for 40 or 80 minutes.
The new sunscreen rules are helpful, but they're not perfect. They don't yet apply to newer formulations, like sprays and powders, so people are still on their own when trying to judge the effectiveness of those products, Rigel says.
The new labels also don't tell you anything about how sticky, gooey, or greasy a product feels, and that's important, Rigel says, since "sunscreens only work if you use them."
Tips for Applying Sunscreen
Once you've found a product you like, be sure to use it correctly. The American Academy of Dermatology offers these tips for proper application.
Use enough. Most adults need a full ounce of sunscreen to fully cover all exposed areas of skin. An ounce is the amount in a shot glass or enough to fully cover the palm of your cupped hand.
Use it early. Sunscreen takes about 15 minutes to absorb into the skin, so put it on before you head outdoors.
Use it often. Sunscreen should to be reapplied every 2 hours, even if it has a high SPF. Be sure to put more on immediately after swimming or sweating.
Don't use expired products. Sunscreen loses its effectiveness when it starts to separate, which happens 2 to 3 years after it was made. Toss any products that are expired, or that look gritty or have changed appearance.
Never rely on sunscreen alone. Experts also advise covering up with sun protective clothing, including a hat with a wide brim and sunglasses. Try to avoid the sun altogether during midday.
SOURCES: Darrell S. Rigel, clinical professor of dermatology, New York University Medical Center.FDA: "FDA Sheds Light on Sunscreens."American Academy of Dermatology: "Sunscreen: How to Apply."
©2013 WebMD, LLC. All Rights Reserved.
Subscribe to MedicineNet's Skin Care & Conditions Newsletter