As it gets colder and we start bundling up in jackets and earmuffs, most of us tend to stop thinking about our sun exposure. After all, how much damage can the weak winter sun cause if you're already covered up from head to toe?
But the sun's rays can be just as harmful when it's cold and cloudy outside. "Any exposed area of your body can still get sunburned," Dr. Apple Bodemer, an associate professor of dermatology at the University of Wisconsin-Madison, told Live Science.
Whether you spend a day on the slopes, skating on a pond or shoveling snow out of your driveway, your face is still getting exposed to the sun's radiation in the form of ultraviolet (UV) light, according to Bodemer. When those UV rays penetrate deep into your skin cells, they can cause DNA damage, she said. [Do Animals Ever Get Sunburned?]
The sun's long ultraviolet A (UVA) waves can cause premature aging, sunspots and wrinkles, while its short ultraviolet B (UVB) rays are notorious for causing skin reddening and burns. (Ultraviolet C, or UVC rays are a third and even shorter type of ultraviolet radiation that is mostly absorbed by the Earth's ozone layer).
Skin damage caused by UV exposure increases over time. "Your skin is like the meter in a taxi cab," said Dr. Darrell Rigel, a clinical professor of dermatology at New York University. "As you get more radiation, the meter goes forward, and the more that happens, or the stronger the radiation, the faster the meter goes."
Eventually, UV-related skin damage can lead to skin cancer. It's the most common type of cancer in the United States. About 3.3 million Americans are diagnosed with basal and squamous cell skin cancers each year, according to the American Cancer Society.
Snow and ice can also make sun damage worse. They reflect up to 80 percent of UV rays that reach the ground, according to the Skin Cancer Foundation. That means that you get hit from two angles: first from the sky and second from the ground, as the rays rebound. And skiers and snowboarders increase their risk of getting sunburned even more because UV exposure increases at higher altitudes.
"Our atmosphere helps scatter some of the UV radiation," Bodemer said. "When you're up at a high altitude, there's not as much atmosphere and you will get more intense UV radiation exposure."
The overall amount of UV rays decreases slightly in the winter because of the angle that the sun's rays hit the Earth, Bodemer said. But people who are exposed to the winter sun — especially those who are prone to burning in the summer — are still at risk of getting a sunburn, she said.
Certain creams and medications, such as retinol products and chemical peels, can also make the skin more photosensitive. Rigel told Live Science. And even tetracycline-based antibiotics, including those prescribed for treating acne or a cold, can increase your sun-sensitivity.
"In general, the biggest factor for sun-sensitivity is how pale your skin is," he said. "But, the reality is that even the darkest [skinned] individual can get sun damage. They might not get it as quickly because they have more natural protection, but even dark-skinned individuals get skin cancer."
Luckily, the solution for protecting your skin is simple: Wear sunscreen every day. Rigel recommended using sunscreen with a sun protection factor (SPF) of at least 30, and going higher if you're planning a vacation at high altitudes. As a rule of thumb, SPF 30 will block 97 percent of UVB rays; SPF 50 will block 98 percent of UVB rays; And SPF 100 will block 99 percent of UVB rays, Dr. Steven Wang, the director of Dermatologic Surgery and Dermatology at Memorial Sloan Kettering Cancer Center in Basking Ridge, New Jersey, told the Skin Cancer Foundation. And, no matter what kind of sunscreen you use, it's important to apply SPF about once every 2 hours, Wang added.
Rigel also suggested looking for sunscreens labeled "broad spectrum" — to protect against both UVB and UVA rays — as well as sunscreens that are water resistant for up to 80 minutes. That way, you can go about your day without it wearing off too quickly.
You don't have to hibernate indoors as long as you protect yourself when you go out, Rigel said. "It always pays to protect yourself."
Original article on Live Science.