Sunscreen Won't Totally Protect You From Cancer

Beach season is just getting started, but before you break out your flip-flops and straw hats, there are some important things you should know about sunscreen — things that might have you seriously reconsidering your sun-protection habits. For example, a recent study in the scientific journal Nature pinpointed a molecular mechanism of malignant melanoma that sunscreen alone might not be able to prevent.

Researchers studied the effects of high-protection sunscreen on mice, finding that mice that were applied with SPF 50 creams developed fewer tumors than the unprotected mice overall, some still developed the cancer.

The researchers were able to pinpoint a specific gene harmed by the radiation, the TP53, which normally helps heal broken DNA and protect against tumor development. Until now, the TP53 gene wasn't clearly associated with melanoma, but the study showed that the gene coordinates with several other DNA mutations that cause nearly half of the deadly incidents of the disease.

While sunscreen significantly reduces the harm done to the TP53 gene, it doesn't always completely eliminate it.

"It's the first experimental evidence that sunscreen actually protects you from melanoma but it also shows that it doesn’t offer complete protection," study author Richard Marais, the director of the Cancer Research U.K. Manchester Institute, told Bloomberg. "You need to use other strategies as well."

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Along with this alarming discovery, there are many common misconceptions about sunscreen. Given that skin cancer is the most common type of cancer in the U.S., affecting more than 2 million people annually, and one person dies of melanoma every hour, you should probably pull up a chair and listen closely.

Choose the Right Sunscreen

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When choosing the right sunscreen that will offer the most protection while doing the least amount of harm to your skin, there are many factors to consider. For instance, the higher the SPF doesn't mean the better the sunscreen. There are two types of harmful ultra-violet rays — UVA and UVB — and SPF only blocks the latter. For protection against both, choose a broad spectrum or multi-spectrum sunscreen.

Other factors to consider are picking sweat- and water-resistant versions — especially if you plan on swimming, avoiding spray products because breathing in the particles can be harmful, and avoiding products that contain Vitamin A. Believe it or not, applying this vitamin on your skin can make it easier for tumors and lesions to develop.

Lastly, be aware of certain toxic chemicals in sunscreen, especially oxybenzone, which is a synthetic estrogen that can penetrate your skin and disrupt your hormones. In some cases, it can even cause cell damage and lead to skin cancer. Look for products with zinc oxide, 3% avobenzone, or Mexoryl SX instead.

Apply — and Reapply — Liberally

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Dermatologists recommend applying an ounce of sunscreen — about the size of a golf ball — onto every exposed area of skin, which includes your ears, the back of your neck, and your feet. Start applying about 30 minutes before you go outside since it takes about that long for it to absorb into your skin.

And don't forget to reapply! You should be doing so every two hours if you're not swimming and every hour if you are. Don't even pay attention to the "All-Day Protection" promise on the bottle.

Sunscreen Isn't Only For Sunny Summer Days

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Contrary to popular belief, sunscreen shouldn't only be reserved for the summer. While it's most crucial on hot, sunny days at the beach, experts strongly suggest wearing sunscreen even on cloudy days and all year long. People seem to forget that the sun is up there 365 days a year, and sometimes its rays are even stronger in the winter when reflected against snow.

American Brands May Not Be Up to Snuff

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A recent report revealed that European sunscreens may be a lot more effective than our American counterparts. In fact, the FDA hasn't approved of a new sunscreen ingredient since 1999. Meanwhile, Europe has approved of several ingredients proven to be effective in protecting against UVA rays. So if you're visiting Europe anytime soon, maybe it'd be a good idea to stock on their sunscreen while you're there.