Just Wondering: Should I Wear Sunscreen Indoors?

Sure, wearing SPF outdoors is a no-brainer, but what about if you're just chilling at home or working in the office? You may be wondering: Should I wear sunscreen indoors? On the one hand, you're obviously not working on your tan while binging Netflix. But then again, wearing sunscreen in winter is a thing so maybe applying it indoors is also? To set the facts straight, we reached out to skincare experts Dr. Marie Hayag and Dr. Elizabeth Hale who let us in on whether you should be lathering up on SPF while inside.

Keep scrolling to learn everything you need to know about protecting your skin from the sun — and other culprits — according to top dermatologists.

Should You Wear Sunscreen Indoors?

The short answer? Yes!

"There are different types of ultraviolet rays that affect the skin," says Dr. Elizabeth Hale, a board-certified dermatologist at Complete Skin MD and senior vice president of The Skin Cancer Foundation. "We mostly talk about ultraviolet A (UVA) and ultraviolet B (UVB) rays." While UVB rays cause sunburns, UVA rays — which have longer wavelengths that penetrate through the clouds and through windows— cause skin aging, she tells us.

"Because UVA (aging) rays penetrate deeper into the skin and cause DNA damage, they break down collagen and elastin," explains Dr. Marie Hayag, a board-certified dermatologist and sunscreen expert in New York City. "This makes them responsible for accelerated photodamage including wrinkles, leathery skin, sunspots, and skin cancer."

And if you've been you've been using prescription or over-the-counter retinoids, taking an oral antibiotic like doxycycline for a skin condition, or doing at-home treatments like chemical peels, your skin is already sensitized to the sun. This makes the UVA rays coming through your window all the more potent and you may experience instant redness and irritation as a result.

Blue Light and Skin Damage

While blue light is a newer phenomenon, there are reports that frequent exposure can contribute to premature signs of aging. "Even short exposures of blue light can increase a generation of reactive oxygen species, which breaks down collagen and elastin, and cause DNA damage, leading to DNA mutations which subsequently can cause skin cancer and aging," says Dr. Hayag. High visible light (HEV) such as blue light, can also affect sleep and eye health, she adds.

Over time, blue light can decrease melatonin levels, which makes it difficult to sleep and kill photoreceptors (light-sensitive cells) in the retina, which are essential to see. This is why you've read about how you shouldn't scroll through social media on your phone right before going to bed.

The Best Indoor Sunscreens

Both dermatologists agree that a broad spectrum physical sunscreen containing zinc oxide and iron dioxide will provide adequate protection from UVA rays and blue light. "There's new data that tints that are present in iron oxide which present in tinted sunscreen and even some foundations can be helpful as an extra layer of protection against visible light," says Dr. Hale. She suggests EltaMD's cult-favorite UV Daily Tinted Broad-Spectrum SPF 40, a moisturizing formula safe for all skin types.

In addition to zinc oxide and iron dioxide, Dr. Hayag says to look for a formula containing antioxidants to block free radicals produced by UV rays and blue light. She's a fan of MDSolarSciences Mineral Crème SPF 50 Sunscreen. It's lightweight and blends into the skin without leaving a white cast. Dr. Hayag also recommends Skinceuticals Physical Fusion UV Defense SPF 50, which contains a plankton extract that is known to increase the skin's resistance to UV- and heat-induced stress.

Just like being outside, it's best to reapply sunscreen every two hours. Consider keeping a brush-on mineral SPF powder for quick touch-ups during the day, suggests Dr. Hale. ISDIN Isdinceuticals Mineral Brush and Colorescience Sunforgettable Total Protection Brush-On Shield SPF 50 both have a mattifying effect and come highly recommended.

VIDEO: When You Apply Sunscreen in Your Skincare Routine Actually Matters A Lot

Outdoor Sunscreen Protection

Wearing outdoor sunscreen is a must for everyone. But despite knowing this, some of us may still experience sunburn or another form of sun damage. That may have to do with our skin tone/type, how often we're exposed to the sun, and whether or not applying we're applying SPF correctly.

"We know with chronic low-level sun exposure you do build a tolerance," says Dr. Hale. "People who work outdoors like farmers are exposed to UV rays every day so when it's really sunny out, they don't burn like someone who usually works indoors. So after hibernating all winter... our skin isn't building up a tolerance." That being said, when you do go outside, you might sunburn more easily.

Also, some people are prone to sun sensitivity and get rashes during the seasonal shift to warmer weather. "Dermatologists call it photodermatosis and there there are different types," says Dr. Hayag. "The most common is called polymorphus light eruption (PMLE) and it affects 10 to 15% of the population, more commonly in fair-skinned women." PMLE manifests in a red, bumpy, itchy rash on the chest, backs of hands, and outer surfaces of the arms and legs, but occasionally can be more severe with blisters. The rash can appear in just 30 minutes of sun exposure and typically gets better as the season progresses.

So to keep your skin protected, apply a solid base coat of SPF before going outside and reapply it every two hours to prevent UV damage to your skin. On top of sunscreen, both dermatologists stress that it's also important to wear a hat, sunglasses, protective clothing, and to stay in the shade when possible.

For an extra layer of protection, Dr. Hale recommends a protective supplement like ISDIN SunISDIN Softgel Capsules or Heliocare Ultra Capsules. These products contain enzymes to help repair cell mutations from the sun. "The thought behind these supplements is that the enzymes will internally repair damage before it occurs," she explains.