Consumer Guide to Sunscreen: Risks & Benefits

Skin cancer is the most common form of cancer in the United States. It’s estimated that one in five Americans will be diagnosed with skin cancer at some point in their lifetim­e. Many people rely on sunscreen to reduce these risks and prevent premature aging.

But recent studies and reports claim that many of the sunscreen products sold in stores don’t work as well as they claim, and certain chemical ingredients in some products may not be safe. Another controversy involves the claim that using sunscreen will lead to low vitamin D levels.

As the Food and Drug Administration looks to update its regulatory requirements for most sunscreen products, Consumer Notice took a hard look at the controversies to see if the science backs up the scary hype.

Our conclusion: Sunscreen is still an important and effective tool to reduce your skin cancer risk, but choosing the right sunscreen and knowing how to properly use it is also key.

To understand how sunscreen works, it helps to understand how the sun’s rays affect us. The sun emits ultraviolet radiation in several different wavelengths that is invisible to the naked eye but damaging to the skin.

UVC rays are the shortest wavelengths of light, but they are also the most damaging. Fortunately, few of them make it through the earth’s atmosphere and most are absorbed by the ozone layer.

UVB rays are longer than UVC rays, and they do make it through the atmosphere. UVB rays penetrate the superficial layers of the skin, causing reddening and sunburn. UVB rays are the most common cause of skin cancer.

UVA rays are less intense than UVB rays but much more prevalent. They penetrate the skin more deeply and play a major role in premature aging. UVA rays are also believed to play a role in initiating the development of skin cancer.

Sunscreen works by blocking and absorbing these harmful rays so they can’t damage your cells.

There are two types of sunscreens: physical sunscreen and chemical sunscreen. Understanding the difference between the two types can help you choose the one that’s best for you.

Physical sunscreen contains active minerals that sit atop your skin’s surface and deflect and scatter damaging ultraviolet rays. Titanium dioxide and zinc oxide are common ingredients in physical sunscreen, or physical blockers, as they’re sometimes called.

Physical sunscreens can be difficult to rub into your skin and sometimes leave a white residue on the skin, though newer physical sunscreens use small particles, or nanoparticles, that are less likely to leave streaks. They also tend to be tolerated better by people with sensitive skin.

Chemical sunscreens, on the other hand, create an extra barrier on the surface of the skin to absorb the sun’s UV rays like a sponge. Common active ingredients in chemical sunscreens sold in the United States include: avobenzone, ensulizole, homosalate, octinoxate, octocrylene or oxybenzone. They are easier to rub into your skin than mineral sunscreens and less likely to leave a visible residue.

Some products contain both physical and chemical ingredients.

In recent years, some health groups, consumer organizations and others have raised concerns about how the chemical ingredients in many sunscreens may affect people’s health. Recent actions and studies by the FDA have added to the controversy and confusion.

In May 2019, the non-profit Environmental Working Group issued its 13th annual guide to sunscreens. The EWG’s 2019 study reviewed more than 1,300 sunscreen products and concluded that two-thirds offer inadequate sun protection or contain worrisome ingredients, such as oxybenzone.

The EWG report came just days after an FDA study published in May 2019 in JAMA found that four chemicals commonly used in sunscreen are rapidly absorbed into people’s bloodstreams. All four chemicals — avobenzone, oxybenzone, octocrylene and ecamsule — exceeded maximum blood concentration limits set by the FDA within one day of being applied.

What this all means, however, is unclear.

The researchers said the clinical significance of this sort of systemic exposure is unknown and should be studied further but advised consumers to continue using sunscreen in the meantime. And dermatologists that Consumer Notice spoke with agreed.

Dr. Joshua Zeichner, the director of Cosmetic & Clinical Research in Dermatology at Mount Sinai Hospital in New York, told Consumer Notice that many questions remain.

He noted that in an FDA study, large amounts of sunscreen were applied to three-quarters of the study subjects’ bodies.  But in the real world, Zeichner said, consumers don’t use that much sunscreen and they don’t usually reapply it religiously every two hours. So it’s unclear how much absorption would occur under normal patterns of usage.

Aside from that, Zeichner said sunscreen’s protective benefits outweigh any potential risks.

“We have not seen any harmful health effects of sunscreen with years of application on millions of people,” he said.

On July 14, 2021, Johnson & Johnson issued a voluntary recall for some of its Neutrogena and Aveeno spray sunscreens after lab testing found low levels of benzene in some samples. The company told consumers to stop using the products immediately and dispose of them properly.

Benzene is a chemical used to make pesticides, rubber, plastics and other products. The World Health Organization and U.S. Department of Health and Human Services have said that benzene can cause cancer, specifically leukemia. Benzene isn’t normally an ingredient found in sunscreen, and J&J is investigating how it got into the recalled products.

According to J&J’s recall statement, the amounts of benzene found in its products shouldn’t cause health problems. But lawyers are already investigating potential sunscreen lawsuits.

Edgewell Personal Care Company added to a recall of its Banana Boat Hair & Scalp Sunscreen Spray SPF 30 in January 2023. The expanded recall included a new batch lot affected by benzene contamination. The original recall was issued in 2022.

An internal review by the company found the source of the benzene was a propellant that sprays the sunscreen out of the can. Edgewell said it does not use benzene in any of its products.

The company offers reimbursement to anyone who purchased sunscreen with the affected lot codes. Consumers may call 1-888-686-3988 for a refund.

Consumers may locate lot codes on the bottom of the can.

Currently, only two common ingredients in sunscreen — titanium dioxide and zinc oxide — are designated as “generally recognized as safe and effective,” or GRASE, by the FDA. Both minerals are physical sunscreens that sit on top of the skin.

Two other ingredients — PABA and trolamine salicylate — are not GRASE and are considered unsafe for use. But consumers have little reason to worry here because both chemicals are no longer available in the United States.

But not enough is known about a dozen other sunscreen ingredients to determine whether they are safe. They include commonly used chemicals, such as avobenzene, homosalate, octinoxate, octisalate, octocrylene and oxybenzone, and less commonly used ingredients, such as cinoxate, dioxybnezone, ensulizole, meradimate, padimate o and sulisobenzone.

Of all those chemicals, oxybenzone has grabbed the most attention. Oxybenzone, which is present in about two-thirds of non-mineral sunscreens, is known to cause allergic reactions. In animal studies, the chemical has been linked to hormonal disruptions, including toxicity to the male reproductive system.

Its effects on humans are unclear, but oxybenzone is absorbed through the skin and has been found in breast milk, amniotic fluid, urine and blood. A 2008 study by researchers at the Centers for Disease Control and Prevention found the sunscreen agent present in the urine of nearly 97 percent of people tested.

Other scientists have detected oxybenzone in fish and waterways across the world, and the skincare chemical has been implicated in the bleaching of coral reefs. The problem is so significant that Hawaii took the unusual step in 2018 of passing a law to ban the sale of sunscreens containing oxybenzone and octinoxate. The ban goes into effect in 2021.

Chemicals aren’t the only concern. Studies suggest that many sunscreens don’t provide as much sun protection as they claim.

In 2017, Consumer Reports tested 60 sunscreen products and found that 38 percent of them were only providing protection at less than half what their SPF label said. It was the fifth year in a row that the consumer group found that many products didn’t live up to their promises.

Following Consumer Reports’ publication of its investigation, several consumers filed complaints against Edgewell Personal Care Company, alleging that the company misleadingly marketed certain Banana Boat sunscreen products as containing “SPF 50+” when they did not.

Some of the complaints have been dismissed following settlement negotiations. The terms of any potential settlements have not been disclosed, however.

Another concern is whether using sunscreen dangerously reduces vitamin D levels.  The crucial vitamin D is produced by the body when skin is exposed to sunlight and low levels have been linked to everything from chronic diseases to bone fractures.

A 2017 review published in The Journal of the American Osteopathic Association said widespread vitamin D deficiencies are likely caused by people wearing sunscreen. The article went on to suggest that people regularly forgo sunscreen because “SPF 15 or more decreases vitamin D3 production by 99 percent.”

But others in the medical community disagree. Dr. Antony Young, a professor and photobiology researcher from King’s College London, told Consumer Notice that sunscreens do have an inhibitory effect but “still allow a lot of vitamin D production.”

Young spearheaded a 2019 study published in the British Journal of Dermatology that examined the vitamin D levels in 20 people who used sunscreen with SPF 15 and 22 people who didn’t use any protection during a week in the sun. At the end of the week, both groups saw an increase in their vitamin D levels.

“The important thing is that one can make ample vitamin D without sunburn,” Young explained. “This is because the UVR dose needed for vitamin D is much lower than that which causes sunburn. For my studies, I estimate about one-tenth of the dose, but this may also depend on the amount of body surface area exposed.”

Young also pointed out that many of the previous studies suggesting that sunscreen has detrimental effects on vitamin D production were done using artificial ultraviolet radiation from phototherapy lamps. The lamps are “nothing like sunlight,” he said, and could produce misleading results.

If your vitamin D levels are low, you can also eat more foods that are rich in vitamin D or take an oral supplement. If you’re concerned about your vitamin D levels, talk to your doctor. He or she can test your levels with a simple blood test and suggest a plan that’s right for you.

Amid all the controversy, the FDA is planning to update its sunscreen regulations and take a harder look at the safety of active ingredients in the products. The move is part of comprehensive reform of how the FDA regulates over-the-counter products and is intended to bring sunscreen standards “up-to-date with the scientific standards,” according to FDA officials.

As part of its efforts, the FDA, which regulates sunscreen as an over-the-counter drug, is seeking more information on 12 common sunscreen ingredients, including oxybenzone and avobenzone.

In the meantime, the FDA encourages consumers to continue using sunscreen and other skin cancer prevention methods.

And, as Zeichner pointed out, consumers have choices. If they’re concerned about chemicals, they can opt for a product that contains zinc oxide or a combination of zinc oxide and titanium dioxide.

Controversies aside, at the end of the day, choosing the right sunscreen is just as important as using a sunscreen at all. But most consumers aren’t savvy when it comes to sunscreen labels.

In 2014, researchers at the Northwestern Medicine dermatology clinic interviewed 114 people to assess their skills at reading sunscreen labels. More than 80 percent of them had purchased sunscreen some time in the past year, but fewer than half understood from the labels how well the product protected against skin cancer, photoaging and sunburns.  And only 49 of the 114 participants understood the meaning of the SPF value.

SPF stands for sun protection factor. But what does that really mean? The SPF number on sunscreen tells you how long UV radiation from the sun would take to damage your skin if you use the sunscreen exactly as directed.

If you apply a sunscreen with SPF 30, for instance, it would filter out about 97 percent of UVB rays and you should be able to stay out in the sun 30 times longer before burning than if you weren’t wearing sunscreen. But it’s important to remember that SPF only applies to UVB rays, and the UVA rays can still wreak havoc.

And sunscreens with higher SPFs only provide marginally better protection. Sunscreen with SPF 100 will not provide twice the protection of a sunscreen with SPF 50. While a sunscreen with SPF 50 would filter out about 98 percent of UVB rays, an SPF 100 would block about 99 percent.

While no sunscreen can protect you completely, most medical experts recommend using a sunscreen with SPF 30 or higher. But don’t rely on SPF alone. SPF primarily measures UVB protection. To ensure you are also getting protection from harmful UVA rays, you need a formula with “broad spectrum” protection.

Broad spectrum sunscreen will protect you from sun-related skin damage as you age, such as wrinkles, age spots and sagging skin, in addition to reducing your skin cancer risk.

It’s also wise to choose a sunscreen that is water resistant. The label will also specify how long the water resistance lasts — either 40 minutes or 80 minutes. After that time period, you’ll need to reapply the sunscreen. The FDA does not allow any sunscreen to claim it is waterproof.

It’s not recommended to use sunscreen on infants who are younger than 6 months old. Instead, it’s best to keep your baby out of the sun entirely.

Hari Cheryl Sachs, a pediatrician with the FDA, explains on the agency’s website that babies’ skin is different from adults’ skin. For one, it’s still developing, and because of that, it’s more susceptible to chemical irritation. Babies also have a higher surface-area to body-weight ratio, meaning that the potential side effects of chemicals in sunscreen could be more toxic in a baby than in an adult.

But even older children can have severe reactions to sunscreen. In March 2019, a Florida mother sued the parent company of Banana Boat sunscreen because she said one of the company’s spray sunscreen products caused her 2-year-old son to develop severe blisters. She told her local ABC news station that the blisters eventually ruptured and caused his skin to peel off.

Others have made similar claims. In 2017, a Canadian mother said her 14-month-old daughter developed caustic burns, swelling and blistering after she applied Banana Boat Kids Sunscreen SPF 50 to her daughter’s face.

Health Canada launched an investigation following the incident and other similar reports of skin reactions suspected of being associated with Banana Boat sunscreen products. But after testing 27 sunscreen products, the agency concluded that there were no serious concerns with the quality of any of the products, according to a 2018 information update.

Health Canada said other factors could have contributed to the reported reactions and the agency is continuing to review the safety of sunscreen products and the risk of skin reactions.

For those reasons, it’s better to keep your babies in the shade and dress them in lightweight clothing with long sleeves and pant legs.

Given all the controversy, some consumers have chosen to go another route and make their own “all-natural” sunscreens. Do-it-yourself personal care products are a growing trend, and Pinterest and other social media sites are awash in homemade sunscreen recipes that use ingredients such as coconut oil, lavender oil, raspberry oil, shea butter and beeswax.

But researchers say these do-it-yourself formulas are a bad idea and that most of these ingredients haven’t been proven to offer effective broadband protection.

Julie Merten, an associate professor at the Brooks College of Health at the University of North Florida, and researchers at Nationwide Children’s Hospital looked at 189 online sunscreen formulas and found that more than two-thirds offered insufficient protection from dangerous UV rays.

“I think it is a risky endeavor because homemade sunscreens haven’t been tested for their true UV protection, water resistance or photostability, which places people at risk for sunburn and even worse — skin cancer,” Merten told Consumer Notice.

Merten said that consumers who are worried about chemical exposure should opt for a mineral blocker.

“The chemical sunscreens have been receiving the most criticism, so the mineral blockers such as zinc oxide or titanium dioxide-based sunscreens would be a great choice,” she said.

When it comes to sunscreen, apply it early and often. You should slather your sunscreen on at least 15 minutes before going outside. This will give your skin time to absorb the product. If you go out too soon after applying it, your skin may still burn.

Be sure to cover all exposed areas of skin while avoiding your eyes and mouth. The American Academy of Dermatology’s rule of thumb is to apply 1 ounce, or the equivalent of a shot glass, to your entire body. Commonly missed spots include: the face, ears, eyelids, tops of your feet, hairline, back of the neck, hands and areas of the head exposed by balding.

In fact, a 2019 study by British researchers found that up to 14 percent of people applying sunscreen — and 20 percent of those using moisturizers with SPF protection — missed covering their eyelid regions.

The American Academy of Dermatology recommends reapplying sunscreen every two hours. You should also reapply it after swimming, when sweating and after toweling off. Water-resistant sunscreens should be reapplied every 40 minutes to 80 minutes, depending on what the label says.

Many people mistakenly think that they don’t need sunscreen if it’s cloudy or cold outside. While UVB rays are weaker in the winter due to the position of the sun, they’re still able to cause damage, and UVA rays are present all the time. So be sure to use your sunscreen daily, all year round.

People often think of sunscreen as the only way to avoid the sun’s harmful rays, but sunscreen alone is never enough.