Tanning can lead to skin cancer and more
Sunburns have long been associated with an increased risk for skin cancer, but tanning raises the risk, too, said Dr Patricia Farris, a dermatologist in Metairie, Louisiana.
Tans and sunburns are caused by exposure to two types of ultraviolet rays emitted by the sun. Ultraviolet B rays cause sunburns, and ultraviolet A rays penetrate more deeply and induce tans. Both types of UV rays can cause DNA mutations that raise the risk of cancer, Farris said.
“When indoor tanning became vogue, they pushed the narrative that tanning could be done safely as long as you don’t burn,” she said. “Almost immediately, dermatologists began seeing younger and younger patients with skin cancers and particularly melanoma.”
UVA radiation injures the skin in other ways, too, said Dr Min Deng, a dermatologist with MedStar Health in Chevy Chase, Maryland. “There’s a whole milieu of molecular consequences,” she said. In addition to directly damaging the DNA, UVA radiation suppresses the immune system in ways that also increase the risk for cancer, she said.
It also ages the skin; UVA rays are involved in “breaking down collagen and elastin molecules and causing wrinkles, brown spots and weathered-looking skin,” Farris said.
What about vitamin D?
Although it’s important to get enough vitamin D — adults ages 19 to 70 should aim to get 600 international units (IU) of vitamin D per day — people often have misconceptions about how best to obtain it, experts said.
Vitamin D is synthesized in the skin after exposure to the sun’s UVB rays. Most adults with lighter skin can typically get enough vitamin D after spending up to 10 minutes outside at midday during the spring and summer months, research has found.
Studies also suggest that sunscreen does not significantly impair the body’s ability to make vitamin D from sunlight exposure, Farris said.
If you have darker skin, your body may not be able to synthesize as much vitamin D from sunlight, so it’s safer to get it from foods like salmon, egg yolks, fortified milk and juice, as well as supplements, Skelsey said.
Older adults also have more trouble synthesizing vitamin D compared with younger people, Skelsey said. So the older you are, the more you will want to consider eating vitamin D-rich foods or taking supplements, she said.
How to stay safe in the sun
To best protect your skin from UVA and UVB rays, use a sunscreen that is labelled “broad spectrum,” Skelsey said; the American Academy of Dermatology recommends SPF 30.
For people with darker skin tones, Deng advises using tinted mineral sunscreens because the iron oxide they contain protects the skin from other wavelengths of light that can contribute to hyperpigmentation and other disorders common with darker skin.
“Patients with deeper skin tones can still get sunburns and develop skin cancers,” Deng said.
Most people woefully under-apply sunscreen, Deng said. “They only apply about a quarter of the thickness that they’re supposed to apply,” she said.
To get appropriate coverage, apply one ounce, or a shot glass worth, of sunscreen over all exposed skin. If using a spray, she recommended spraying just a couple of inches from the skin and then rubbing it in with your hands.
Most people also don’t reapply sunscreen nearly as much as they should, Deng said. If you’re swimming, getting splashed with water or sweating, you should reapply every hour, even if it’s a waterproof sunscreen, she said. If you’re not getting wet, you should reapply every two hours.
The American Academy of Dermatology also recommends sun-protective clothing with its UPF, or ultraviolet protection factor, on the label. “Sun-protective clothing, hats, beach umbrellas, sunglasses, tinted car windows are all helpful,” Skelsey said.
This article originally appeared in The New York Times.
Written by: Melinda Wenner Moyer
Photographs by: Justin J Wee
©2023 THE NEW YORK TIMES
