How did sunscreen get so confusing?

Despite the extremely well-established science linking sun exposure to skin cancer, bad sun safety advice on social media simply will not stop — and a lot of people are buying it. In several recent surveys, between one and three out of every 10 adults believed a range of falsehoods about sunscreen and sun exposure; a few days ago, the Cleveland Clinic felt compelled to plead with people not to do something called “beer tanning.” 

Young people are especially likely to believe misleading messages about sun exposure, although they don’t have a monopoly on misunderstanding — or miscommunicating — the science; middle-aged podcast hosts (and frequent peddlers of pseudoscience) Joe Rogan and Andrew Huberman have also done their share of spreading inaccurate information. Many experts also point to TikTok as the source of the wildest rumors and speculation about sunscreen.

Sun safety fallacies have been around for decades, but they got a boost five years ago after a flurry of confusing actions and statements on sunscreen by the Food and Drug Administration. Then, last year, multiple aerosol products, including a few sunscreens, were found to be contaminated by benzene — a known carcinogen — leading to widespread recalls. Additionally, a growing body of science suggests there are benefits to getting a little sun, although not all countries’ public health authorities embrace that science equally. A recent article in the Atlantic highlighted evidence suggesting a range of benefits associated with UV radiation. While a consortium of Australian public health groups recommends a modest amount of sun exposure to residents on the basis of some of that evidence, American public health authorities don’t.

It’s no wonder so many people are confused about what’s true and what’s not about sunscreen. Understanding what’s behind some of the more common misleading statements about sun safety — and why people fall for them — can help.

4 sunscreen facts

Sun exposure causes skin cancer — and sunscreen prevents it

Michelle Wong, a cosmetic chemist based in Sydney, Australia, has been correcting sunscreen misperceptions for years on her YouTube channel, Lab Muffin Beauty Science. One of the worst that continues to dominate: “Sunscreen is worse for you than skin cancer, or sunscreen causes skin cancer — yeah, I think it’s always those ones that seem to get the most traction,” she says.

People making this false claim sometimes point to data showing the more than three-fold rise in US rates of the dangerous skin cancer melanoma between 1975 and 2018, a period over which sunscreen technology evolved considerably. Although trends that occur simultaneously are often unrelated, people sometimes suggest (without evidence) that more sunscreen is to blame.

A key data point they’re missing: Melanoma isn’t increasing everywhere. In fact, in Australia, where sunscreen culture is perhaps stronger than in any other country, melanoma has been on the downturn since 2005. In 2021, 70 to 80 percent of Australians said they used sunscreen at least sometimes.

Moreover, multiple studies have linked sun exposure to a variety of skin cancers, while plenty of other research shows sunscreen prevents multiple types of skin cancer.

Chemical and mineral sunscreens are both safe — and chemical may be more effective

There are two categories of sunscreens. Mineral formulations rely on flecks of minerals spread on top of the skin to physically reflect the sun’s rays; zinc dioxide and titanium dioxide are the two ingredients typically used in these products. Meanwhile, chemical sunscreens contain substances the skin soaks up, which absorb the sun’s radiation as it hits the skin; these include avobenzone, oxybenzone, and a range of other compounds.

In 2019, when the FDA was moving to update its sunscreen guidelines, it established a threshold — a very low one of just half a nanogram per milliliter — past which these ingredients would need to be further studied to determine if their absorption had any effects. Data the FDA published the following year showed all the chemicals tested blew past that threshold, leading to a furor about chemical sunscreens. 

These findings didn’t invalidate all the safety data the FDA already had on these products, they just meant the agency needed more studies to understand if the bloodstream absorption of these chemicals was meaningful in any way.

So far, studies trying to link chemical sunscreen ingredients with bad health outcomes in animals and humans have been too low-quality to add much to what we know. Meanwhile, we know for certain that sunscreen has immense protective benefits for reducing cancer risk.

Which is better for you? Wong prefers chemical sunscreens, “just because there’s so many limitations with mineral sunscreens that are kind of inherent” to their underlying structure. That is, it’s hard to formulate mineral sunscreens such that their particles get distributed evenly on the skin, so they often don’t work as well.

Ultimately, however, the sunscreen that’s best for you is the one you’ll actually use.

You still get the benefits of occasional sun exposure even if you’re lathered up with sunscreen

There’s a strong body of evidence proving the benefits of UV radiation on bone health, mood, circadian rhythms, and vision, as noted in the Australian sun exposure guidelines. There may also be some benefit to the immune system, although the data to support that is less clear.

Wearing sunscreen doesn’t block those benefits, says Wong. For starters, although it’s clear vitamin D deficiency is associated with sun avoidance and wearing full-body clothing that blocks the sun’s rays, research doesn’t link such deficiencies with sunscreen use. “No one actually applies sunscreen 100 percent correctly — there’s always lots of gaps where UV can get through and produce vitamin D,” she says. 

SPF 50+ is better than SPF 50

Our imperfect application is also the reason why high-SPF sunscreen — even above 50 — is actually better than SPF 50. In the places where your sunscreen application is a little half-assed, an imperfectly smeared SPF 100 will still offer some protection, while an SPF 50 in the same scenario offers substantially less. 

In 2007, the FDA said it wouldn’t allow sunscreens to be labeled with SPFs higher than 50 out of concern the claim was misleading. However, research has shown higher SPFs do translate to more protection: In a study published in 2017, about 200 people in Vail, Colorado applied SPF 50 sunscreen to one side of their face and SPF 100 to the other; the next day, 41 percent of them were sunburned on their SPF 50 side, compared with 14 percent on their SPF 100 side.   

The inclination to believe sunscreen rumors has complicated origins

Why is there such an appetite for misleading information about sunscreen?

Kathleen Jamieson, a misinformation researcher who directs the Annenberg Public Policy Center at the University of Pennsylvania, says part of the appeal may relate to people’s innate suspicion of synthetic chemicals. “There is some disposition, just as humans, to reject [a product] on the grounds that it’s not natural,” she says — and on the other hand, “the sun is natural.”

American public health experts also haven’t hammered the sunscreen messaging the way authorities have in Australia, where sun protection culture is incredibly strong. Generally speaking, the public knows “virtually nothing” about public health, says Jamieson, “unless it’s been told to them a lot.”

Skin cancer is also a smaller public concern in the US than it is in Australia, where it occurs at some of the highest rates worldwide. Because the nation has some of the highest levels of UV radiation in the world, about 66 percent of Australians will get skin cancer in their lifetimes, compared with 20 percent of Americans. “The way you build trust is to have a circumstance in which it becomes relatively clear that people who followed the health guidance benefited, and those who didn’t all died,” says Jamieson. Perhaps because skin cancer feels like less of a crisis in the US — at least for now — it’s less likely Americans feel the urgency to follow health guidance on preventing it.

There may also be something about the relatively balanced message Australians get about sun exposure that makes them more likely to trust its source. In the 1990s, the country experienced a resurgence of rickets, a bone disease related to vitamin D deficiency, which is caused by extreme sun avoidance. Since then, Australian public health experts have attempted to balance strong sun safety education with messaging encouraging a modest amount of sun exposure, says Wong. The nation’s latest recommendations even include a series of complicated grids intended to help people with different shades of skin determine how many minutes they should spend in the sunlight depending on where they live and how much of their skin is covered. The guidelines take into consideration the fact that people with darker skin tones are at lower risk of sunburn and skin cancer than people with lighter skin tones, and can safely withstand more exposure.

Meanwhile, Wong has seen some American dermatologists recommend people wear sunscreen all winter, even indoors (which the science says is rarely necessary), and few US sun safety recommendations make mention of the benefits of getting just a little bit of sunlight.

“Sometimes when there’s a very black-and-white approach, people can sense that it’s BS,” says Wong.

Despite all the things Australian public health has gotten right about communicating sun safety, misunderstandings about sunscreen have long been pervasive in the Australian public. In 2017, nearly half of Australian adults didn’t recognize daily sunscreen use was safe. 

That was before TikTok became the cultural force it is today. We can’t blame influencers for everything.