Skin cancer is prevalent in the United States, and still there are many misconceptions about skin protection — especially when it comes to sunscreen.
There are plenty of things people aren’t aware of when it comes to how sun exposure can affect the skin, says Dr. Adam Friedman, professor and chair of dermatology at GW School of Medicine and Health Sciences. From where on the body you should apply sunscreen to how often you should be reapplying throughout the day.
A fact that would surprise many people when it comes to sunscreen, Friedman says, is what SPF actually protects against.
“SPF only refers to UVB, the type [of sun rays] that burn,” he says. SPF doesn’t factor in ultraviolet A radiation which can penetrate into the skin deeper than UVB rays.
UVA rays are “actually more associated with accelerated skin aging. It damages collagen, elastin. [It’s] also associated with skin cancer, but it doesn’t burn like ultraviolet B does,” Friedman says.
The tricky thing about UVA rays is that they can affect your skin health even when you’re indoors, he explains.
“When you stand next to a window, UVB might be filtered out, but UVA isn’t. So you can get exposure and not even realize it,” Friedman says.
“UVA gets through clouds, so it’s kind of the silent killer. You’re getting exposed and being harmed, and don’t even feel or know about it.”
Friedman recommends using sunscreen with SPF 30 or higher for stronger protection from UVB rays, which is also the recommendation of the American Academy of Dermatology.
“I do push for higher SPFs. There’s really no difference in the feel and the texture or cost. It’s more that I know you’re not going to put the right amount on, so at least it keeps you in a range that is still going to be effective,” he says.
It’s just as important to make sure you’re using a sunscreen that has broad-spectrum protection, meaning it offers protection against UVA and UVB rays, he adds.
On most days, Friedman applies sunscreen only in the morning, “but I don’t go outside at all, and I’m not really near windows,” he says. If you’re planning to be outside for most of the day or spend extended periods of time near windows, reapplying sunscreen often can offer more protection.
“Technically you should be reapplying every two hours. I say technically, because I’m a realist and who’s going to actually do that,” Friedman says. “Do the best you can.”
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