How Safe Is Your Sunscreen? 10 Facts That Will Surprise You

Sunscreen is hands-down the most important product you should use this summer. But just because it protects your skin from the sun’s harsh rays doesn’t mean it’s necessarily good for your skin. Below, we’re unveiling surprising facts you need to know about your SPF.

1. Some sunscreens don’t protect you from everything

Young woman with sun shape on the shoulder

Your sunscreen needs to block two types of rays. | iStock.com/RossHelen

The sun’s harsh rays aren’t created equal. In fact, there are two types you need to protect your skin from: UVA, which can seep deep into your skin and cause premature aging, and UVB, which burns your top layer of skin. The problem is, some sunscreens only cover UVB, not UVA. For lasting protection, Dr. Joel Cohen told U.S. News & World Report to pick formulas that are labeled “broad spectrum” because they actually protect your skin from both rays.

2. It might be prohibiting your body’s ability to generate vitamin D

hand squeezing sun block

If you don’t eat enough vitamin D, you might need to rethink your diet. | iStock.com/verona_S

Your body produces vitamin D3 when it’s exposed to the sun, which is just another reason you should spend more time outside. But did you know slathering on sunscreen can hinder your vitamin D intake? “It is possible that the sunscreen will inhibit some of the generation of active vitamin D in the skin,” Dr. Richard D. Granstein told The New York Times.

That being said, your sunscreen is still important. There are tons of foods that contain vitamin D — think cheese, beef liver, and egg yolks — so it’s best to pile on the SPF and find your vitamins elsewhere.

3. It might be hurting the environment

Beach accessories.

Not all sunscreen is great for the environment. | iStock.com/KristinaJovanovic

Consider your sunblock an environmental Catch-22. It might be keeping your skin safe, but we may have reason to believe it’s hurting the ocean’s ecosystem. Some evidence indicates even the small traces of your sunscreen’s chemicals can kill coral. We would hate to think our sun safety is ruining an entire ecosystem. Let’s hope we can find an ocean-friendly alternative, stat.

4. Those aerosol cans might not be safe…

Woman applying suntan spray onto her legs

It might be time to rethink spray sunscreen. | iStock.com/stefanamer

Aerosol sunscreen is the obvious choice for anyone who wants to apply sunscreen quickly and forgo the milky residue most cream formulas leave behind. But not so fast: Your aerosol spray has a darker side. Those spray-friendly bottles are usually packed with alcohol and, while Glamour reports they’re safe for your skin, they could irritate your lungs and seep into your bloodstream if you breathe in these harsh formulas.

5. … and are also flammable

Woman sitting on deck chair

Aerosol products are flammable, so be careful! | iStock.com/jacoblund

Another reason to rethink your aerosol sunscreen? It might be flammable. The Huffington Post reports a man supposedly caught on fire after applying aerosol sunscreen before grilling. Since those spray cans are frequently filled with different forms of alcohol, the logic’s there. Just stay far away from the grill while at the beach.

6. It won’t protect you forever

woman lying on the beach in the hat

Please remember to reapply. | iStock.com/Foremniakowski

Anyone who has ever suffered a bad sunburn knows it’s crucial to reapply your SPF throughout the day, but how often? If you’re lounging pool-side, but not going in, your SPF can protect you for up to two hours. Want to take a swim? Your sunblock will only protect you for 40 to 80 minutes. The next time you go for a swim, lather up as soon as you return to land.

7. It’s not actually sweat-proof

woman running

Your sunblock really can’t last through that summer run. | iStock.com/lzf

Don’t expect that SPF you rubbed on before a summer 5K to last very long. There’s a big difference between water-proof and water-resistant, the latter being more appropriate for most sunscreens. According to Everyday Health, the sun care industry is taking big steps toward getting such labels off your SPF because it’s simply not true. Considering how much we sweat outside, this one is scary.

8. It can irritate your skin

woman applying sunblock on the beach

Some sunscreens can harm your skin. | iStock.com/VladTeodor

If you never scanned your sunscreen’s ingredients label, you should. Everyday Health says some formulas are packed with oxybenzone, which can cause allergic reactions, and retinyl palmitate, which can speed up the development of skin tumors. Rest assured, not all sunscreen is bad; the website goes on to recommend formulas that use zinc oxide and titanium dioxide as active ingredients instead.

9. The number of SPF doesn’t matter…

woman on beach applying sun block

SPF 100? Not worth it. | iStock.com/CentralITAlliance

… well, not entirely. While there’s a big difference between your SPF 8 and SPF 30, Business Insider reports anything higher than SPF 50 will only give you slightly better protection. You end up thinking your skin is totally safe while it’s actually burning to a crisp. Regardless of your SPF number, make sure to reapply every couple hours.

10. You need to wear it all the time

Woman hands putting sunscreen

If you’re going to be outside, you need to wear sunblock. | iStock.com/travnikovstudio

Sunscreen is only necessary for extended time outside, right? Think again. Even if you’re not at the beach, pool, or park, it’s still important to use sunscreen. Your skin is your body’s largest organ and all that sun could potentially lead to wrinkles, aging, or worse. So why would you risk it? There are tons of moisturizers on the market that are infused with SPF. Lightweight and hydrating, they’ll keep your skin protected no matter the season.

Follow Kelsey on Twitter @Kmulvs and Instagram @Kmulvs