The Real Reason You Should Be Wearing Sunscreen Indoors

If you are spending the day without setting foot outdoors for whatever reason, you may have decided this is the best time to be your comfiest self. So, if you were at home, you'd probably ditch the suit for day pajamas, the heels for thick socks or comfy slippers, and dump the makeup and go bare — or at the very least, throw on some moisturizer. But dermatologists say you need a layer of sunscreen to go on top of that.

Wearing sunscreen indoors may sound very weird, but it's also very important. While your windows can protect you from the sun's UVB rays, they actually don't do much to filter UVA rays, and that's the type of sunshine that could cause the most damage to your skin (via The Cut). Not only do UVA rays degrade your skin's collagen, and potentially leave you with dark spots, wrinkles, and weathered-looking skin, but extended exposure to UVA rays also puts you at risk of developing skin cancer (via Allure).

Sunblock protects you from UV and blue light exposure

It's especially important not to skip the sunscreen indoors if you're sitting next to a window, whether you are at home, or in an office. New York dermatologist at Mount Sinai Hospital Joshua Zeichner emphasized to Allure, "UVA light penetrates right through window glass. So sunscreen is definitely useful even if you're inside. If you're sitting near the window at work, or are next to a window at the gym, you are actually exposing yourself to UVA light, which is responsible for premature aging and skin cancers."

Wearing sunscreen indoors doesn't just protect you from UVA ray exposure, it also shields you from blue light, the glow emitted by all your electronic screens, from laptops, to tablets, to smartphones. There isn't enough research out there to show exactly what blue light might do to our skin, but there are indications showing blue light can also damage our skin's collagen. If anything, blue light already impacts our skin indirectly by suppressing our natural melatonin production, and preventing us from getting a good night's sleep — and we know what that does to our looks.

Skin experts say you won't go wrong if you use SPF 30 to protect yourself from light damage when you're indoors. And if you are sitting near a window, you'd need to put sunscreen on every two hours, just as you would be doing if you were outdoors.