If you work from home, you’ve probably wondered if the perennial advice to wear sunscreen every day applies to you. After all, you barely ever leave the house, and you’re not even the type to sunbathe by the window. We hear you, but we’re here to tell you that yes, this advice does apply to you. If you have windows (and we hope you do), you need to be wearing sunscreen indoors. Confused about the whys and hows? Then keep reading for our deep dive into the greatest mystery of the working-from-home lifestyle.
Why do I need to wear sunscreen indoors?
Long story short, there are two types of sun rays: UVA and UVB. Whereas UVB rays are responsible for sunburn, UVA rays are the main culprits of photoaging, which manifests in the form of hyperpigmentation (melasma and dark spots), wrinkles, and unevenly textured skin. UVA rays can also contribute to skin cancer, which should be the main reason you choose to protect yourself from them.
Window glass can filter out UVB rays, but UVA rays will pass through unaffected. This means you won’t get a sunburn sitting by the window with your laptop, but you may be inadvertently increasing your risk of developing pigmentary conditions over the long term.
So, how can I protect myself?
Step one is simple: wear sunscreen on the areas not covered by clothing, such as the face and hands, and reapply every few hours. Any sunscreen is better than no sunscreen. Step two may sound more complicated (but we’ll explain): wear a broad-spectrum sunscreen.
Early sunscreens weren’t expected to target UVA rays, so they were simply rated on their ability to ward off UVB rays (that’s what the SPF number means). This was bad news for those of us trying to figure out whether to wear sunscreen indoors, since we were already getting the UVB protection we needed from our windows. Science marches on, however, and nowadays we are all well aware of the dangers of UVA rays. Researchers, formulators, and customers alike all agree that we want–or better yet, we need–sunscreens that protect against both types of sun rays. That is what “broad-spectrum” means: a sunscreen that protects against both UVB and UVA rays.
How can I find broad-spectrum sunscreen?
Broad-spectrum sunscreen is (fortunately) becoming the norm, so you won’t have to search far and wide for a product that protects you from both UVB and UVA rays. Most will simply claim to be “broad-spectrum” on the label, and you can trust that information to be accurate.
If you’re looking for a more specific system, there are two to keep an eye out for. The Japanese system uses the letters “PA” followed by plus signs to indicate how much UVA protection a product offers. You should be looking for products rated PA+++, high UVA protection, or PA++++, extremely high UVA protection.
The European Union uses an alternate system: according to EU recommendations, the UVA protection for each sunscreen should be at least a third of the labeled SPF. (That means that a product with a SPF of 30 should have a UVA protection rating, or PPD, of 10.) A product that achieves this requirement will be labelled with a UVA logo that features the letters “UVA” printed in a circle.
