Summertime Safety: Life-Saving Facts about Sunscreen You Need to Know

Summertime means different things to different people. But one thing summer should mean for everyone is sun protection, namely sunscreen. Keep reading to learn which SPF you should be using (page 4) and why sunscreen isn’t waterproof, no matter what the label says (page 6).

Sunscreen is an allergen

Woman choosing sunscreen

Woman shopping for sunscreen | RossHelen/Getty Images

  • Fun fact: Don’t forget to apply sunscreen to your lips, ears, hairline, neck, feet, and hands.

Use sunscreen and break out in a rash? You may be allergic to sunscreen. A sunscreen allergy can also show up after years of use, according to Everyday Health. The two ways an allergy can manifest itself are through a contact rash or a contact photoallergy, Anna Feldweg, MD, a clinical instructor of medicine at Harvard Medical School and an attending physician in allergy and immunology at Brigham and Women’s Hospital, told Everyday Health.

Hint: Find out if you’re allergic to sunscreen.

Are you allergic to sunscreen? The telltale signs

Woman wearing hat applying sunscreen

Woman applying sunscreen | LiudmylaSupynska/iStock/Getty Images

Signs of a contact allergy are swelling, itching, and fluid-filled blisters, according to Everyday Health. In a contact photoallergy, sunscreen chemicals, and sunlight cause a reaction “so you get the rash where the sunscreen was applied but only once the skin has been exposed to the sun,” Feldweg told Everyday Health.

Hint: Don’t forget to do this one thing before buying sunscreen.

Check the expiration date

Young woman applying sunblock cream on legs

Sunscreen | Fizkes/iStock/Getty Images 

  • Fun fact: Stores may sell sunscreen at a clearance rate because of the expiration date.

Leftover sunscreen from last summer may not be good, according to the Center for Disease Control (CDC). Like other products, sunscreen has an expiration date. You can ignore the expiration dates on some things but not sunscreen. Always check the date before tossing a bottle of sunscreen in your beach bag.

Hint: These two words must be on the SPF’s label.

Look for ‘broad spectrum’ sunscreen


Sunset | Jeka1984/iStock/Getty Images

  • Fun fact: Scalp sunscreen products exist so you can protect your head and avoid greasy hair.

When shopping for sunscreen look for “broad spectrum.” Broad spectrum sunscreen protects skin against both UVA and UVB rays, according to Everyday Health. And don’t skimp on the application. “I tell people that they should apply a marble-sized amount for their face, ears, and neck, and a golf-ball size (or shot-glass size) for the full body,” Dr. Joel Cohen, spokesman for the American Academy of Dermatology and director of Aboutskin Dermatology and Derm Surgery, told U.S. News & World Report.

Hint: Use this level of SPF.

Why you should use SPF 50

Woman hands putting sunscreen

Sunscreen at the beach | travnikovstudio/iStock/Getty Images

“The 30 blocks out about 97 percent of UV rays,” Francesca Fusco, MD, assistant clinical professor of dermatology at Mount Sinai School of Medicine in New York, told Everyday Health. “SPF 15 blocks out only 93 percent,” she said. And SPF 50 “blocks out 98 percent of UV rays. When in doubt, reach for SPF 50. And don’t bother with SPF 2-4, it’s like applying body lotion.

Hint: Don’t fall for this sunscreen myth.

No sunscreen is waterproof or sweatproof

young man swiming in oceans water

Man swimming | IakovKalinin/Getty Images

  • Cover scars with SPF because skin cancer is “more likely in those spots because the skin is already damaged,” according to U.S. News & World Report.

Sunscreen manufacturers can’t label sunscreens as “waterproof” or “sweatproof,” according to the U.S. Food and Drug Administration (FDA). “All sunscreens eventually wash off.” For that reason, manufacturers may put “water-resistant” on labels after they’ve been tested.

Hint: Sunscreen may be harming you.

Sunscreen may contain harmful chemicals

Sun screen cream

Sunscreen | Bet_Noire/Getty Images

  • Fun fact: Dogs can get skin cancer too. It’s most common in the mouth or on toes.

In a test conducted by the non-profit organization, Environmental Working Group (EWG), sunscreens contained “potentially harmful chemicals,” according to Scientific American. Chemicals included Benzophenone, homosalate, and octyl methoxycinnamate — also known as octinoxate — “which are known to mimic naturally occurring bodily hormones and can thus throw the body’s systems out of whack.” Others contained Padimate-0 and parsol 1789, which may cause “DNA damage when exposed to sunlight.”

Hint: Look for these two ingredients when buying sunscreen.

Read the ingredients

Sunscreen product

Natural sunscreens | lenta/Getty Images

  • Fun fact: Apply sunscreen before going outside. SPF needs time to soak in.

After studying 831 sunscreens, the EWG recommended SPFs containing zinc oxide and titanium dioxide, according to the Scientific American. Alba Botanica, Avalon, Badger, Burt’s Bees, Juice Beauty, and Kabana are a few of the sunscreen brands the EWG recommended on their Skin Deep Cosmetics Database.

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Read more: Don’t Make These 5 Sunscreen Mistakes and Destroy Your Skin