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Let’s start with the bad news: The sunscreen you’re used to relying on for beach days probably isn’t going to cut it in the mountains.
For starters, there’s the sheer intensity of the sun at altitude. For every 1,000 feet you gain in elevation above sea level, the intensity of the sun’s rays increase by up to 10 percent. So if you’re skiing in Breckenridge, Colorado at 10,000 feet, you’re dealing with UV radiation that’s up to 100 percent stronger than sun at sea level—so twice as intense. Add the effects of snow reflection, and that percentage jumps even higher.
“High altitude is where you’ll find the absolute most intense challenge to your skin, far more than surfing on the equator at noon,” says Steve Johnson, founder and general manager of Sol Sunguard. Adding insult to injury, “Most sunscreen is tested at sea-level,” he says. “That’s at a 100-percent UV standard, not additional intensity you’re getting on a sunny day at 10,000 feet.”
So if you’re getting burned on the mountain despite wearing sunblock, it might not be because you forgot to reapply. Instead, it could be because your sunscreen chemicals disintegrated under a blast of UV rays way stronger than they were ever intended to withstand.
This is the issue with chemical sunscreens, Johnson says. One of two categories of sunscreens, chemical sunscreens rely on molecules that seep into the skin, absorb UV radiation, and release it as heat. These formulas take 20 to 30 minutes to kick in. Once they’ve absorbed too much UV radiation, the molecules decompose and the sunscreen stops working just about immediately, Johnson explains.
Physical sunscreens, on the other hand, rely on minerals like zinc oxide and titanium dioxide to reflect sunlight, acting like a shield between your skin and UV rays. These slowly wear out or wear off over time, but there’s no “sudden, catastrophic failure” like you’ll find with their chemical counterparts, Johnson says.
Most sunscreens that are thin and easy to apply, seem to “disappear” into the skin, or are advertised as “nourishing,” “moisturizing,” or “anti-aging” are chemical sunscreens. That means that at altitude, many are little more effective than face lotion, Johnson says—they’re just cosmetics. And while the “disappearing” effect feels nice, it means that once the formula is absorbed, there’s no layer left to protect your skin from getting windburned or drying out, the other skin hazards at altitude.
So, what’s the solution? First, choose a physical sunscreen over a chemical formula at altitude, Johnson recommends. Higher SPF formulas are better than low-SPF formulas provided the manufacturer performs adequate testing. Finally, durability is paramount.
“Is it water soluble? Will it sweat off? Is it durable against abrasion? These are the three things that make a high-altitude sunscreen more effective,” Johnson says. He recommends looking for sunscreens with a thicker consistency and that have some adhesive agents like methacones.
“I would say that if you find a sunscreen with zinc oxide and methacones, then great,” he says. But, of course, testing compliance varies widely by brand, so while you should always buy from a brand you trust when your health is at stake, there’s no substitute for healthy skepticism and a little personal testing. “Don’t trust the marketing,” Johnson says. “Trust performance.”
But it always helps to start with a few recommendations. Here are three of our favorite picks for high-altitude protection.
Sol Sunguard Altitude SPF 40 High Mountain Sunscreen and Wind Barrier
Sol Sunguard Altitude SPF 40 was designed with the demands of high-altitude sports in mind. The Zinc-based, broad-spectrum formula protects against both UVA and UVB rays and doesn’t degrade in high-UV conditions like you might find at 10,000 feet. Next-level waterproofing and adhesion keep the active ingredients on your skin even when you break a sweat on warm spring days or swipe at your runny nose one too many times. And unlike many other sunscreens, Sol Sunguard’s Altitude SPF 40 is hand-tested at altitude—which means you’re actually getting 40 SPF protection even when you’re blessedly far from sea level.
Thinksport Safe Sunscreen SPF 50+
Thinksport Safe Sunscreen’s spreadable consistency, sweat resistance, fragrance-free formula, and clean ingredients list (no parabens or chemicals proven to harm coral reefs) earned it top marks from our testers. Like Sol Sunguard, Thinksport uses a non-nano zinc oxide as its active ingredient and cetyl dimethicone to prevent drying in high-altitude conditions. Like many other mineral-based sunscreens, it feels thick upon application. That said, this one seems to spread more smoothly and evenly than most and doesn’t leave skin white when it’s fully rubbed in. (Thinksport also makes a lightly tinted version, which looks even more transparent on most complexions.) Though it isn’t specifically designed for high-altitude sports, we found the 50+ formula adequate for long days above treeline.
Bare Republic Mineral SPF 50 Sport Sunscreen Stick
Sometimes the wind is blowing, the air is cold, and the last thing you want is to take your gloves off and rub something cold and wet on your face. Enter Bare Republic’s Mineral SPF 50 Sport Sunscreen Stick. We loved the pocket-sized, mess-free stick for reapplying with gloves on. A water-resistant, 25-percent zinc oxide formula (the highest of any sunscreen in this list) protects against both UVA and UVB rays. A clean ingredients list gives this one eco-cred, and the light vanilla coconut scent is a nice touch, too.