Sunscreen: Fact or Fiction—How to Protect Your Skin


It’s the time of year when we start thinking about the beach, picnics, summer vacations, and lots of outdoor activities…and that means thinking about sunscreen. Of course, sunscreen is important year round, yet summer seems to be the time we focus on this important product and how to protect your . Since we’ve got your attention, let’s check out the fact or fiction of sunscreen and see how you fare.

Before we jump into the game, it’s important that you understand ultraviolet (UV) rays. The two forms of UV rays are UVA and UVB. UVA rays are associated with wrinkles, aging skin, and suppression of the immune system. These rays are longer than UVB and they can penetrate the dermis, which is the thickest layer of skin.

UVB rays are the ones that turn the top layer of your skin lobster red. It has a big role in the development of skin cancer. Obviously, you need protection against both types of rays.

Do I need to wear sunscreen when I’m driving and it’s sunny?

Yes, especially if your arm or that of your passenger is resting on an open window. However, the window does not need to be open for you to be receiving UV rays. The same applies in your home, office, or other inside environments where the sunlight comes in through windows. Although UVB rays cannot get through glass, UVA rays can. You should apply skin protection on exposed areas when you are indoors if you have sunlight exposure.

A high SPF means it offers more and longer protection

No. In theory, using a sunscreen that has an SPF (sun protection factor) of 100 would allow you to expose your skin 100 times longer before you would sunburn, according to the Environmental Working Group. In other words, if you normally get red after 30 minutes, you could stay in the sun for 50 hours. Obviously that’s not true.

When you properly apply a sunscreen with an SPF of 50, it should block 98 percent of UVB rays, while a product with an SPF of 100 will block 99 percent. Basically, what you need is a sunscreen with an SPF between 30 and 50, and you should get adequate protection. SPF 30, which blocks 97 percent of UVB rays, is the most common level for the majority of people.

Another issue concerning high SPF products is that you may be lulled into thinking, “I’m okay, I don’t need to reapply it often.” This thinking can result in staying in the sun too long without proper sunscreen and ending up with a sunburn. The EWG also points out that sunscreens with high SPF values have higher concentrations of chemicals, which may present health risks when they are absorbed into the skin. So in the end, a lower SPF product, say SPF 30 rather than SPF 70, is a better choice.

Expired sunscreen is perfectly fine to use

No. If your sunscreen is near expiration or has passed expiration within the last few months, you may not get all the protection you would from an in-date product. In a pinch, it’s better than nothing. However, generally you should discard any product that is past its expiration date.

According to the Mayo Clinic, sunscreens are made to keep their original strength for up to three years. If you buy a product that doesn’t have an expiration date on the label, make a note of when you bought it on the bottle. You also should discard sunscreen that has changed in consistency or color.

Chemical sunscreens offer better sun protection than mineral sunscreens

No, and here’s why. Overall, mineral sunscreens are less likely to have irritating or harmful ingredients. That’s because mineral sunscreens are made with physical blockers, which include zinc oxide and/or titanium dioxide. These ingredients reflect UV rays. Chemical-based sunscreens use ingredients such as avobenzone, homosalate, oxybenzone, and/or octinoxate, which absorb UV rays.

Because chemical-based products absorb UV rays instead of blocking them, UVA rays can reach deeper layers of skin and damage it. Mineral-based sunscreens, on the other hand, protect against both UVA and UVB, according to dermatologist Jeanette Jacknin, MD, author of Smart Medicine for Your Skin.

I don’t need to worry about the chemicals in sunscreen

Yes, you do. In a new study (May 2019), investigators with the Center for Drug Evaluation and Research reported that levels of certain sunscreen ingredients entered the bloodstream after just one day at levels significant enough to cause an investigation. The one ingredient that was especially worrisome, oxybenzone, was at a 50 to 100 higher concentration than the other three (avobenzone, ecamsule, and octocrylene). The Food and Drug Administration has asked that these ingredients be evaluated by sunscreen makers before they can be given the label GRAS (generally recognized as safe).

In addition, the FDA issued a proposed rule on February 19, 2019, in which it noted that:

“Of the 16 currently marketed active ingredients, two ingredients—zinc oxide and titanium dioxide—are GRASE (generally recognized as safe and effective) for use in sunscreens; two ingredients—PABA and trolamine salicylate—are not GRASE for use in sunscreens due to safety issues. There are 12 ingredients for which there are insufficient safety data to make a positive GRASE determination at this time. To address these 12 ingredients, the FDA is asking industry and other interested parties for additional data.”

A mineral sunscreen must contain zinc oxide

No. Mineral sunscreens can contain zinc oxide and/or titanium dioxide, so you may or may not have zinc oxide in your mineral sunscreen. When it comes to effectiveness, zinc oxide reportedly has a slight advantage over titanium dioxide. While the latter can block UVB and short-wave UVA, it is not as good as zinc oxide at blocking long-wave UVA.

Is calling a sunscreen reef safe a marketing ploy to sell more sunscreen?

No. Our coral reefs are in extreme danger. They are a critical habitat for a wide range of marine life and also protect beaches from erosion. Scientists are working on a number of ways to help save these essential reefs, and banning certain sunscreen ingredients is just one of them, but an important one. Oxybenzone and octinoxate (benzophenone-3 and octyl methoxycinnamate, respectively). These chemicals cause deformities, DNA damage, bleaching, and death in coral. The ban is scheduled to go into effect in Hawaii on January 1, 2021. In Florida, the state’s Coral Reef Conservation Program urges divers to not use sunscreen that contains oxybenzone to help protect the Florida Reef Tract.

I can skip sunscreen on cloudy days

No. Just because the sun isn’t out, doesn’t feel hot, or isn’t strong doesn’t mean the UV rays are taking a holiday. In fact, up to 80 percent of the sun’s rays can pass through the clouds. That means you still need to use sunscreen when it is cloudy.

Sunscreen prevents the body from absorbing

Theoretically yes. If you used sunscreen all of the time, it could prevent you from getting enough vitamin D. However, because sunlight can penetrate clothing, people don’t typically use skin protection all the time, and sunscreens can become less effective over time, you can still make some vitamin D from the UV rays that do reach your skin. Approximately 15 to 20 minutes of unprotected sun exposure daily can create an adequate amount of vitamin D in the body.

The bottom line

Sunscreen is a necessary tool in the prevention of skin cancer and other assaults to the skin. In order to use these products properly, it’s important to understand their strengths and limitations. Overall, sunscreen should be used regularly, even on cloudy days; the safest and more effective sunscreens are mineral-based; and an SPF of 30 to 50 is typically adequate.

[Editor's Note: Goddess Garden has a whole line on natural sunscreens for babies, kids and adults and recently added SPF50 to their products. They have also been instrumental in the passing on laws that ban oxybenzone sunscreens in various states.]

Read this next:

Ban Sunscreen With Chemicals That Harm Marine Ecosystems

6 Tips for Healthy Skin All Summer Long

8 Foods That Brighten Your Skin

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American Academy of Dermatologists. Sunscreen FAQs
Florida Department of Environmental Protection. The South Florida Reef ambassador initiative—become a corral champion! Coral Reef Conservation Program
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Environmental Working Group. What wrong with high SPF?
Food and Drug Administration. FDA advances new proposed regulation to make sure that sunscreens are safe and effective. FDA news release 2019 Feb 21
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LaMotte S. Sunscreen enters bloodstream after just one day of use, study says. CNN 2019 May 6
Lish K MD. FAQs about sunscreen.
Nall R. Titanium dioxide vs zinc oxide in sunscreen. Livestrong
Schultz R. Does natural sunscreen hold up against regular sunscreen? Shape 2017 Jun 28
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Deborah is a freelance health writer who is passionate about animals and the environment. She has authored, co-authored, and written more than 50 books and thousands of articles on a wide range of topics. Currently, she lives in Tucson, Arizona.