By Caitlin Hagan
CNN Medical Associate Producer

Few things can make me as happy as a hot summer day at the beach. I'm a total sucker for sunshine but unfortunately, until recently, I had not been able to spend much time romping around in the sand. So when I packed my beach bag I made sure to bring not one, not two, but three bottles of sunscreen: plenty of protection to make sure my skin was sunkissed, not sunburned. Sounds like a great plan, right? Except all three had different SPFs, some but not all were broad spectrum, and one was just for my face. For a woman who wants to avoid a sunburn but maximize her vacation, things got a little confusing.

Apparently my dilemma is not that uncommon. Dr. Ariel Ostad is a dermatologist and assistant professor of dermatology at New York University who deals with this issue often. According to him, which SPF, or sun protection factor, you choose is not as important as what kind of radiation you're being protected from. SPF protects you from ultravoilet B, or UVB, radiation, the kind that causes sunburns. But when you are outside in the sun, your skin is also exposed to another type of damaging radiation. "Make sure your sunscreen contains an ingredient to block UVA radiation. 'Broad spectrum' is really the term that people should be looking for," advises Ostad. Since UVA rays are responsible for premature wrinkles and sun spots, it is best to keep your skin out of their reach.

But why isn't SPF the top priority? According to Ostad, the higher and higher SPFs for sale now are more about marketing than actual increased protection. It turns out that a sunscreen with a high SPF such as SPF 80 does not offer exponentially more protection, as most people think it does. According to the American Academy of Dermatology, there are diminishing returns the higher the SPF reaches. Sunscreen with SPF 30 lets in about 3 percent of the sun's harmful rays and a sunscreen with SPF 85 does not do much better, letting in more than one percent. "Anything above an SPF 30 makes absolutely no difference," says Ostad.

Keep in mind though, not all sunscreens are equal, even if they are broad spectrum. People worried about breaking out after slathering on sunscreen should opt for non-comedogenic products, which means that they won’t block pores. Sunscreens with an active ingredient of zinc oxide or titanium dioxide are good bets for people with sensitive skin who worry about too many chemicals in their products.

Now I know that the next time I head out for a day in the sun, there's no need for confusion (or three bottles).

How do you keep your skin protected?

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