Sunscreens favored by consumers aren’t always recommended by dermatologists, according to a recent analysis of Amazon.com‘s top-rated products.
Among 65 sunscreens rated most highly by shoppers, 26 didn’t meet American Academy of Dermatology guidelines, according to a study published in the Journal of the American Medical Association Dermatology. Getting the right product can help protect against skin cancer, the study said. The most common cancer in the United States, it affects 1 in 5 Americans, according to the academy.
Most of the products that fell short lacked water and sweat resistance but met other criteria, including having an SPF of 30 or higher and protecting from ultraviolet A and ultraviolet B rays.
While people who aren’t swimming or sweating might not need to worry about water resistance, the results point to the complexity of choosing from among the billion-dollar industry’s thousands of products and their advertised benefits, said Dr. Steve Xu, the study’s lead author and a resident physician in dermatology at McGaw Medical Center of Northwestern University in Chicago.
“It’s really hard to cut through all that noise to figure out ‘What do I need,’ and I hope our paper can help do that,” Xu said.
An Amazon search turned up 6,500 sunscreens, according to the paper. In reviews of the listed lotions, creams, moisturizers and sprays, shoppers focused on how easily they could apply the products, how they felt on their skin, whether they were greasy, how they smelled and how they looked.
“This went on very smoothly and easily and left my skin with a gently matte finish,” wrote a reviewer of one product, according to the paper. “It left a white residue all over my face,” wrote a reviewer of another product. “It absolutely reeks,” wrote another.
After cosmetics, shoppers commented most on performance.
“It has the broad-spectrum rating from the (Food and Drug Administration) that means it protects from the UVA and UVB,” wrote one, accurately. “I’m absolutely obsessed with this SPF,” wrote another. “I was able to stay out at my children’s soccer games for the entire afternoon with no sunburn,” wrote another.
Skin compatibility, product ingredients and expense were other big factors.
Dermatologists should pay attention to consumers’ preferences, Xu said. More important than picking the perfect sunscreen is using the product correctly, according to Xu and other dermatologists.
“The most important factor is that you’ll use it regularly,” said Dr. Laura Ferris, an associate professor of dermatology at the University of Pittsburgh and UPMC. “A very good sunscreen that sits in the bottle is not going to protect you from skin cancer.”
Dermatologists recommend applying sunscreen — about an ounce, or a shot glass full for head-to-toe coverage — 15 to 30 minutes before going outside. Users should reapply the product every two hours, or every 80 minutes if they are swimming.
Additional precautions should be taken.
“Sunscreen isn’t the whole picture,” said Dr. Nicole Velez, director of dermatologic surgery at Allegheny General Hospital. “You can’t put on sunscreen and then spend 10 hours in the sun and expect to avoid skin cancer.”
Velez recommends avoiding sun during peak hours and finding shade. She said her family wears sun-protective clothing to the beach.
Sunscreens marketed as organic are no more effective than regular products, and the term can be ambiguous, dermatologists said.
In the study, researchers divided products into physical and chemical blockers: Physical blockers usually contain titanium oxide or zinc oxide and sit on top of the skin, while chemical blockers are absorbed into the skin, Xu said.
“There really isn’t too much of a performance difference in real-world situations,” he said.
SPF refers only to protection against ultraviolet B, or UVB rays, Velez said. But UVA rays penetrate the skin more deeply than UVB rays and are just as dangerous, she said. Sunscreen should be broad-spectrum, meaning it blocks UVA and UVB rays, dermatologists said.
The FDA tests sunscreens to verify that labels of SPF, or sun protection factor, are as advertised. Independent testing by Consumer Reports has found the SPF can vary from what is labeled. Xu, Ferris and Velez said there are variables involved in testing SPF in a lab but that the AAD recognizes SPF labels as reliable.
The study found that prices had little to do with product quality as measured by consumers or the AAD. Some of the cheapest products were found to be among the best.
“You want to choose a product that you like and that you are going to use,” Velez said.
Wes Venteicher is a Tribune-Review staff writer. Reach him at 412-380-5676 or [email protected].