Sunscreen is one of our best defenses against the sun’s harmful ultraviolet rays, but over the past few years it has been in the news for potential health concerns.

In May 2021 Valisure—an independent company focused on pharmaceutical transparency—detected benzene contamination in 78 sunscreen and after-sun care products from a number of brands. Benzene is a known carcinogen, meaning it can cause cancer, and is linked to a number of other short- and long-term health problems. Many product recalls followed, particularly of aerosol sunscreens.

But approved sunscreen ingredients also made headlines that year, following a statement from the Food and Drug Administration that said many of them cannot be considered safe, based on either poor safety data or a lack of data altogether.

Ditching sunscreen altogether isn’t a good option: UV rays from the sun are known to cause skin cancer and premature skin aging. For instance, several studies have shown that UV exposure increases a person’s risk of developing melanoma, an aggressive form of skin cancer that more than 90,000 people in the U.S. are expected to be diagnosed with each year. So whenever you head outdoors, here’s what to know about the different categories of sunscreen available, what active ingredients could be of concern, what dermatologists recommend and use themselves and why there seem to be so many more sunscreen options outside the U.S.

What types of sunscreen are on the market?

Sunscreens are broadly divided into two categories: mineral and chemical. Active ingredients in chemical sunscreen are carbon-based and include compounds such as avobenzone and oxybenzone. Mineral sunscreens are not carbon-based and include two compounds: titanium dioxide and zinc oxide. Both mineral and chemical sunscreens protect wearers from UV rays. Although mineral sunscreens are often described as solely reflecting UV light and chemical sunscreens are frequently described as absorbing it, mineral sunscreens do both.

Joshua Zeichner, director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City, says that chemical sunscreens typically offer superior aesthetics, compared with mineral sunscreens, which can feel a bit heavier and sometimes leave the skin white and pasty. Chemical sunscreen also allows for a higher SPF, or sun protection factor, which is a measure of how much UV radiation is needed to cause a sunburn on sunscreen-coated skin versus unprotected skin. A higher SPF generally means more UV protection, but after about SPF 30, the differences in protection are more modest. “The reason that you don't see ultrahigh SPF levels with mineral sunscreens is because it would require so much of the mineral that it would be like applying a zinc paste onto the skin,” Zeichner says.

“Chemical sunscreens are generally more common [and] cheaper and can be easier to rub into the skin,” says Shreya Patel, a dermatologist at Affiliated Dermatologists & Dermatologic Surgeons PA’s office in Morristown, N.J. But for people with sensitive skin and conditions such as eczema or psoriasis, mineral sunscreens can be less irritating. “Certain chemical sunscreens are typically associated with skin allergies or irritation, including those with oxybenzone, cinnamates and octocrylene,” Patel says. “We recommend using mineral sunscreens in these cases, as these products rarely cause skin reactions.”

Should you avoid certain sunscreen ingredients?

In the U.S., the over-the-counter monograph for sunscreen products—a document that defines the safety, effectiveness and labeling of active ingredients—lists 16 such ingredients that are categorized as GRASE (generally recognized as safe and effective) and therefore do not require FDA approval to be used in a new product. But on September 24, 2021, the agency put forth a proposal that would amend the monograph.

The FDA proposed that chemical sunscreens that contain aminobenzoic acid (PABA) and trolamine salicylate are not GRASE. PABA’s risks include severe sun sensitivity, and trolamine salicylate can cause serious bleeding, vomiting and—in extreme circumstances—death. “These ingredients don’t need to be removed from the market until we finalize our proposal,” says Theresa Michele, director of the Office of Nonprescription Drugs at the FDA. But currently “there are actually no marketed sunscreen products containing these two ingredients.”

Citing a need for more data in its September 2021 document, the agency also proposed “not GRASE” status for the chemical ingredients oxybenzone, avobenzone, cinoxate, dioxybenzone, ensulizole, homosalate, meradimate, octinoxate, octisalate, octocrylene, padimate O and sulisobenzone. Clinical trials led by FDA scientists have shown that many of these active ingredients are absorbed into the bloodstream at levels above the concentration threshold the agency has set for determining potential cancer risk. But it’s unclear whether having those active ingredients in the bloodstream is dangerous. “Insufficient data does not mean that’s a conclusion by us that they’re unsafe,” Michele says. “It just means we’re requesting additional data.”

In 2021 bans on the sale of sunscreens containing oxybenzone or octinoxate went into effect in Hawaii and Key West, Fla., but not because of human health—the ruling followed years of laboratory studies that showed the compounds are harmful to corals and other marine life.

The FDA’s September 2021 proposal included keeping the status of the two remaining active ingredients—zinc oxide and titanium dioxide, the two compounds used in mineral sunscreens—as GRASE. “And because of the statement that the mineral sunscreens are considered safe and effective, the chemical sunscreens now have a bad reputation,” Zeichner says. But “as a dermatologist, I personally do recommend chemical sunscreens on a daily basis, and I use them on myself and on my family.”

What do dermatologists recommend?

“Ultimately the best product is the one that you’ll actually use,” Zeichner says. He adds that it is important to look for a product with at least SPF 30 that says “broad spectrum” because that means it protects against both ultraviolet A and B (UVA and UVB) rays. “My personal opinion is to choose a product that has the highest SPF level possible,” Zeichner says, because people rarely put enough of it on or reapply it frequently, and the SPF will be quickly diluted if too thin a layer is applied or if the sunscreen is sweat off.

“I recommend my patients use whatever sunscreen they feel comfortable applying to their skin and that they will use regularly,” says dermatologist Samer Jaber of Washington Square Dermatology in New York City. “I personally prefer the mineral sunscreens with zinc oxide or titanium dioxide as they are less irritating. But as long as my patients use sunscreen, I am happy.”

Patel also defers to her patients’ preference, as long as the sunscreen is broad-spectrum and has an SPF of at least 30. “The most important thing is to use sunscreen every day on at least all the sun-exposed areas of the body—including the face, ears, neck and hands,” she says.

Wearing protective clothing, finding shade and avoiding peak sun hours around midday are also effective ways to protect against sun damage.

Why are there many more sunscreen options outside the U.S.?

“To qualify as a drug in the U.S., something has to make a drug claim, which sunscreens do,” Michele says. They claim to help prevent sunburn or to decrease the risks of skin cancer and early skin aging caused by the sun.

“Because sunscreens are considered drugs in the U.S., they are tightly regulated and require extensive testing to be approved,” Jaber says. This means fewer available active ingredients for sunscreen manufacturers to work with in the U.S., compared with other countries, including the U.K., where sunscreens are considered cosmetics and don’t undergo the same extensive regulation.

In the U.S., the last approval for an active sunscreen ingredient was in 1999, “whereas in Europe and Asia, there have been numerous new sunscreen ingredients approved that offer better UVA protection, are longer lasting [and] less greasy and have a better texture, which makes them more likely to be applied,” Jaber says. Regulations are not necessarily lacking in other countries—in the European Union, for example, sunscreens still need to be approved by the European Commission following assessment by the Scientific Committee for Consumer Safety. And in Japan, the Japanese Ministry of Health, Labor and Welfare regulates cosmetics under the Pharmaceutical Affairs Law. But comparatively, FDA requests for additional safety data have frustrated many, and even led to the creation of the Public Access to SunScreens (PASS) Coalition, an alliance between public health organizations, sunscreen manufacturers and others focused on increasing access to more effective sunscreens. That includes active ingredients that offer better UVA protection.

Longer-wavelength UVA rays penetrate deeper into the skin than shorter-wavelength UVB rays, although both types are known to cause skin cancer. It would be an important step forward if U.S. sunscreens could provide better UVA protection, Zeichner says. “I think we’re all eagerly awaiting the FDA to allow newer ingredients to be incorporated into U.S. sunscreens,” he says. “And I know that a lot of the cosmetic companies are waiting for that as well. They have new formulations waiting in the wings.”

“The cost of testing can be very expensive and thus discourage international brands from obtaining approval in the U.S.,” Patel says. But, she adds, there is an upside to the stricter regulation. “This also helps ensure that the active ingredients the population is exposed to are safe and protective,” she says.

“We continue to invite sunscreen manufacturers to submit data showing that sunscreens that aren’t yet on the market here are generally recognized as safe and effective,” Michele says. “So far, we haven’t gotten that data.”