Retiring your knit sweaters and breaking out nontoxic pedi supplies? Then it’s also time to answer the upcoming season’s important question: How do I choose the safest sunscreen?

The FDA’s new sunscreen requirements ease the challenge by making labels less misleading and products more effective. Under these rules, sun care companies must test products for “broad-spectrum” coverage, which means protection from once-ignored UVA rays (those linked to skin cancer) in addition to UVB (responsible for burns). Sunscreens also have to quantify “water-resistant” claims and eliminate labels touting SPFs of 50 or higher (after 50, additional protection is miniscule). 

But the requirements won’t clear up all confusion—and they don’t guarantee safe sunscreens—so ask these questions to find the healthiest, most effective sun care products.

Are mineral sunscreens always better?

The short answer is “yes.” The Environmental Working Group (EWG) recommends mineral sunscreens (those containing zinc oxide or titanium dioxide) for safe and lasting UV protection minus harsh chemical ingredients. But not all mineral sunscreens are created equal, says Sonya Lunder, an EWG senior analyst.

Though there’s no agreed-upon standard for optimal broad-spectrum coverage, a concentration of titanium dioxide (a weaker UV protector than zinc oxide) in the 2 percent range typically won’t offer adequate protection, says Lunder. Compare sunscreens using the EWG’s Sunscreen Guide (ewg.org/sunscreen), which ranks products based on broad-spectrum UVA and UVB coverage, as well as ingredient safety. 

Am I getting enough UVA protection?  

When you get burned, UVB rays are the culprits. A sunscreen’s SPF, which stands for Sun Protection Factor, measures protection from UVB rays only, not UVA rays, which make up about 95 percent of those that reach Earth and are actually more detrimental to long-term health.

Responsible for a seemingly harmless tan, UVA rays penetrate the skin more deeply and generate free radicals in your skin, leading to wrinkling and skin cancer over time. The most effective ingredient for UVA protection is zinc oxide, according to Lunder. And although products frequently include the chemical avobenzone for UVA protection, it absorbs rays rather than reflecting and scattering them. Avobenzone also is unstable, so it may break down into unknown chemicals.

Raise your protection odds by reapplying sunscreen frequently, or better yet, by avoiding the sun altogether midday, when the rays are stronger. “Consumer expectations [of sunscreens] are too high,” Lundy warns, adding that there is no evidence proving that sunscreens prevent malignant melanoma.

Are higher SPFs superior?

After the FDA nixed SPFs higher than 50 because they aren’t better at fighting rays, SPF recommendations have shifted. Lunder says that products with moderate SPFs may actually be safer and more effective than higher-SPF products, because greater UVB protection can often mean lower UVA protection.

In fact, SPFs lower than 50 can be safer and more efficacious when it comes to broad-spectrum coverage, says Lunder. “You’re better off in the low SPF category knowing that you’re getting more of that balance. As SPFs move higher, you’re proportionately not getting as much of that UVA protection.”  She generally recommends choosing products with SPFs between 15 and 30 to achieve the best balance of UVA and UVB protection.

What to know about nanoparticles and oxybenzone

What about nanoparticles?

Many sunscreens make non-nano claims, indicating they don’t contain the tiny particles used to achieve sheer coverage. But the FDA doesn’t require nano testing or enforce labeling standards. “Nano is really tricky because there’s no formal definition of what size is a nano particle,” Lunder says. Sunscreen makers often define nano as anything less than 100 nanometers. 

But should you always avoid nanoparticles? The EWG maintains that they’re safe in lotion form but not in sprays, which may cause lung damage when inhaled. Research implies that particles larger than 30 nanometers aren’t absorbed by the skin. However, 2012 research published in the Chemical Engineering Journal indicates an unforeseen risk of titanium dioxide sunscreen nanoparticles: Chlorine may strip the nanoparticles’ coating and react with water, forming compounds that could contribute to skin damage and even cancer.

If you have concerns, look for products that provide specific nano information on labels; you might even want to contact companies directly.

Is oxybenzone that bad?

If you need more reason to switch to mineral sunscreens, this should do the trick: Approximately 52 percent of beach and sport sunscreens use oxybenzone, a benzophenone chemical that the EWG gives a high-hazard “8” ranking for its link to cellular damage, endocrine disruption, and skin absorption.

Recent research published in Environmental Science & Technology showed that benzophenone chemicals may have stronger estrogenic activities than even bisphenol-A (BPA). According to the study, a form of benzophenone called benzophenone-1, which forms when the body breaks down oxybenzone, was significantly associated with endometriosis. What’s more, the Centers for Disease Control reports that benzophenones are found in the urine of 97 percent of Americans.