The most common cancer in the United States is skin cancer and sunscreen is the most effective way to prevent getting it.
However, recent research found that some ingredients from those sun-protecting lotions are being absorbed into your body.
Is this a risk to your health?
The researchers say these drugs are present in the blood after sunscreen application at levels that would, under current Food and Drug Administration (FDA) guidelines, trigger a requirement for further safety testing.
“Sunscreen’s last review as a safe treatment or requiring increased FDA regulation was in the 1970s,” noted Dr. Richard Torbeck, a board-certified dermatologist with Advanced Dermatology PC.
“A prudent approach is now being undertaken to make sure that proper regulations are in place to protect the consumer,” he told Healthline. “As more data comes out about chemical UV-blockers, a more definitive statement can be made.”
Researchers used data from an open-label, randomized pilot study with 24 adult participants to find out how much of these chemicals were absorbed, as well as how they move through the body during maximum sunscreen use.
The researchers said they found that the concentration of chemicals increased from day one of the study to the fourth day, indicating the substances build up over time.
There were also persistent levels of the chemicals in the blood after discontinuing the sunscreen use.
“All sunscreens are absorbed into our skin [to] some degree,” Torbeck said. “Physical blockers that can be thick and appear white or opaque are less likely to be absorbed by the skin. Chemical blockers tend to have an additive that allows them to spread on the skin more easily. Alcohols in lotion formulation or aerosol sprays may increase the penetration into the skin especially when applied to hot, sweaty, or irritated skin.”
However, experts say sunscreen users shouldn’t panic.
“There is currently no evidence that sunscreen ingredients currently approved by the FDA cause harmful effects,” Dr. Tanya Nino, a dermatologist with St. Joseph Hospital in Orange, California, told Healthline.
The study required participants to apply sunscreen four times a day to 75 percent of the body’s surface area for four days.
Participants were separated into groups, each receiving a different combination of active sunscreen ingredients within a commercially available cream, lotion, or spray.
Researchers said their analysis showed that almost all participants had systemic levels of sunscreen drugs exceeding the FDA threshold after a single day of sunscreen application.
However, the researchers wrote that “The systemic absorption of sunscreen ingredients supports the need for further studies to determine the clinical significance of these findings. These results do not indicate that individuals should refrain from the use of sunscreen.”
At the same time, the researchers added that the findings raise important questions about sunscreen and the way the sunscreen industry, clinicians, and regulatory agencies evaluate the benefits and risks of this topical medication.
Plus, there’s always the risk versus benefit factor of sunscreen.
“Exposure to ultraviolet radiation is still the single most preventable risk factor for skin cancer,” Nino said. “Melanoma, the most deadly type of skin cancer, has been directly linked to ultraviolet exposure in the vast majority of cases.”
According to the researchers, this study had two important limitations, the biggest one being that it was conducted indoors.
None of the participants were exposed to heat, sunlight, and humidity, which could have changed the rate each ingredient was absorbed.
The study did find consistent absorption of the sunscreen active ingredients across the different types tested.
Also, the study wasn’t designed to examine differences in absorption by sunscreen formulation, skin type, or a participant’s age.
Sunscreen was first approved as an over-the-counter medication for the prevention of sunburn before modern methods of drug evaluation were used.
Currently, drug manufacturers must demonstrate through research in humans that the benefits of a drug outweigh the risks when used as intended for a specified population.
Sunscreen does meet the current requirements for safety.
“At this time, yes, because without robust data that is shown by rigorous prospective studies it is difficult to quantify the risk,” said Torbeck.
“We have strong evidence, a greater burden of proof of concept, for UV exposure’s role in development of skin cancer. I recommend to all my patients to utilize any and all sunscreen compared to outright avoiding based off of chemical blocking UV filter’s risks,” he said.
The Environmental Working Group (EWG) in Washington, D.C., has reviewed the data on nine chemicals most commonly used in over-the-counter sunscreen.
They think that there may be cause for concern.
“Laboratory studies indicate that some chemical UV filters may mimic hormones, and physicians report sunscreen-related skin allergies which raises important questions about unintended human health consequences from frequent sunscreen application,” the EWG states on its website.
They also consider oxybenzone to be the most worrisome.
“Oxybenzone has received attention as a potentially harmful substance since studies have demonstrated its absorption into the body through the skin,” Nino said. “However, the level of absorption and its biological effects on the human body have yet to be determined. Recently, the FDA has requested more information be obtained.”
A 2017 study found oxybenzone could cause allergic skin reactions as well as react with chlorine to produce hazardous byproducts in pools and waterways.
“The EWG recommends avoiding oxybenzone due to the possible risk, similar to BPA in plastic water bottles,” Torbeck said. “In my practice, I try to guide patients to use physical blockers like zinc and titanium dioxide that are generally recognized as safe and effective ingredients.”
“Generally recognized as safe and effective” (GRASE) is how the FDA classifies drugs safe for human use.
Only two ingredients currently used in sunscreen meet that standard: titanium dioxide and zinc oxide.
Besides oxybenzone, the
Among the concerns are that oxybenzone ”is absorbed through the skin to a greater extent than previously understood,” according to a proposed FDA rule.
However, Torbeck emphasized the importance of UV protection.
“There are very few instances where sun exposure without UV protection is warranted,” he said. “One simple way to reduce risk is to wear sunscreens in daily moisturizers with safe and effective UV filters. Brands like ELTA MD, Think brand, Aveeno, Neutrogena, and Eucerin have daily moisturizers with safe ingredients like zinc and titanium dioxide.”
New research finds that ingredients in sunscreen are absorbed into the body and can even build up over time.
Some of these ingredients may affect your health.
The FDA is currently reviewing the safety of many of these chemicals, but sunscreen still meets current standards for safety.
Experts say the benefits of using sunscreen far outweigh any risks that some ingredients that block UV light may present.