5 burning questions on sun protection

Are spray sunscreens safe? Is 30 SPF enough? Our skin expert has the answers.
© MSN Healthy Living // © MSN Health

Summer is all about having fun in the sun, but if you’re smart, you’ll do it safely. That means practicing good sun sense whenever you or your family head outdoors. But if you still don’t know your SPF from your UVB, don’t worry. We called on dermatologist Dr. Joshua Zeichner, Director of Cosmetic and Clinical Research at Mount Sinai Medical Center in New York City, to get answers all your questions about sun protection. Here is a round-up of your most burning questions and Dr. Zeichner’s expert answers.

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Q: Are spray-on sunscreens considered unsafe?

A: The idea of being able to spray on sun protection is almost irresistible. It’s fast, you don’t have to get your hands all gooey and you can easily get it on all those impossible-to-reach places on your back and shoulders. But you do need to take some extra care when using this mode of protection. The biggest issue: not using enough. “Unlike creams, which can be accurately measured out, it can be challenging to know how much spray you’ve put on,” Zeichner says. His tips for getting the best coverage out of your spray:

• Keep the nozzle just two inches away from your skin when applying.
• Spray each area of skin for at least one second.
• Apply to small areas at a time and immediately rub in with your hand to make sure you haven’t missed any skin.
• Don’t apply it outside in the wind or you risk having most of it blow away instead of landing on your skin.

But don’t be surprised if your favorite spray disappears from the store at some point in the future. The FDA is currently studying the safety and efficacy of sprays — looking at both how well they protect skin and whether using a spray could lead to inhaling anything potentially dangerous into your lungs.

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Q: I keep hearing about new rules for sunscreen labels. What’s really changed?

A: The changes that you’ll find on sunscreen bottles are mandated by the FDA and have been years in the making. The idea is to standardize the wording you see on labels and make it easier to know what you’re really getting inside the bottle.

“In the past, some of the wording has been confusing and the claims misleading,” Zeichner says. “These changes are designed to help clarify things for the consumer."

One of the biggest changes is that sunscreens with an SPF lower than 15 are required to include a warning that they will not protect against skin cancer. Another key wording change is that sunscreens can no longer claim to be waterproof or sweatproof. Instead, they can be labeled sweat- or water-resistant for a time limit of either 40 or 80 minutes, indicating how long you can be wet before needing to reapply. And any product that uses the phrase “broad spectrum” on the label has to have been proven to protect against both UVA and UVB rays.   

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Q: Will a higher SPF number protect my skin longer than one with a lower number?

A: SPF stands for “sun protection factor” and the number refers to the amount of time you can theoretically spend in the sun without burning (so if you would normally turn red in 20 minutes, using SPF 15 would protect you for 15 times that long). But these numbers can be misleading.

First of all, the SPF measurement only relates to UVB rays, so that number means nothing when it comes to how much protection you’re getting from UVA rays. “And no matter how high the number, nothing blocks 100 percent,” Zeichner says. SPF 15 blocks about 93 percent of UVB rays; SPF 30 blocks 97 percent; 50 blocks 98 percent. “You don’t get much more protection with really high numbers — and you may have a false sense of how covered you are — which is why most dermatologists recommend SPF 30,” Zeichner says.

The real key is making sure you apply enough to actually get the protection promised by the SPF number. According to Zeichner, you need to use an amount the size of a nickel for your face, a quarter-size amount for your chest and another for your back, a nickel for each arm and a quarter for each leg. “If you apply less, the potency will be diluted out,” he says. And you need to use that much again each time you reapply (which should be every two to three hours that you’re outdoors, plus any time you swim or sweat).

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Q: What does “broad spectrum” really mean?

A: “There are two type of UV rays — UVB, which cause burning, and UVA, which cause skin cancer and skin aging — so you need to make sure your sunscreen protects against both,” Zeichner says. Since the whole system for coming up with the SPF rating of a sunscreen is based solely on the UVB rays it screens out, you will need to see the words “broad spectrum” on your sunscreen label to know that it has been proven to also provide protection against UVA rays.

In addition to seeing that phrase, you can also check the list of active ingredients for ones that have been shown to provide good UVA protection. These include titanium dioxide, zinc oxide, avobenzone and Mexoryl. Finding one or more of those in the mix is a good indication that the sunscreen will indeed provide the broad spectrum protection it promises.

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Q: My child fights me every time I try to apply sunscreen. Help!

A: No matter how much you try to make a game out of it, chances are that your kid will continue to fight the sunscreen routine. And while children might not understand the necessity, you should know that even one blistering sunburn during childhood more than doubles the risk of getting melanoma (the most deadly form of skin cancer) later in life. So deal with the tears, and slather it on!

“Try using a stick formula for the face since it’s less likely to get into their eyes and sting,” Zeichner says. “It’s also great for small, often neglected, areas like the ears, part in the hair and tops of feet.”

Zeichner also recommends using hats and sun-protective clothing in addition to a head-to-toe coat of sunscreen. “Hats with broad brims protect the face, scalp, ears and even the back of the neck,” he says. For clothing, dark colors in closely woven polyester materials will provide significantly more protection than light-colored, loose weaves such as cotton. More and more, you’ll see clothing and swim shirts rated with a UPF number. “That stands for the ultraviolet protection factor of the fabric and indicates that it’s been tested and proven to provide that amount of sun protection,” Zeichner says.

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