Chemical vs physical SPF: What’s the difference?

Tanlines may be on trend every summer, but sunburns and skin cancer never are. Sunscreen should be a staple in our skincare routines, but oftentimes we neglect to apply, reapply or even purchase.

Discovering one that works into your daily routine can keep your skin looking young and cancer-free.

But with an endless aisle of options, finding one that works for you can be difficult.

One way to figure out which one works for you is knowing the difference between the two types of Sun Protection Factor (SPF): chemical and physical.

Before we get into the details here’s a little refresher: The Food and Drug Administration (FDA) recommends using at least SPF 15 on the reg, but anything higher than 50 doesn’t necessarily provide more protection. Ultraviolet A (UVA) rays penetrate deeper into the skin and promote signs of aging, while ultraviolet B (UVB) rays affect the surface level and can cause cancer. You want a sunscreen that defends against both, called broad-spectrum.

Sunbum 30 SPF (left), chemical sunscreen, and Alba Botanica (right), a physical sunscreen. Photo by Alexis Paige

Physical SPF is like applying a shield onto your skin. It immediately blocks both UVA and UVB rays — hello, broad-spectrum! — using the ingredients zinc oxide and titanium oxide. Sometimes referred to as mineral sunscreen, these natural ingredients can protect your skin and have been known to not break you out.

But, it’s never is going to soak into your skin like you may be used to. As it sits on top of your skin, a slight white tint can occur. But if you’re applying makeup afterwards it shouldn’t be a big issue.

Chemical SPF is made from, well, chemicals. Not (all) harmful chemicals though. You’ll see words like octocrylene, avobenzone and octinoxate in the ingredients list. Unlike physical, you have to let it sit for about 15 minutes prior to sun exposure for it to work properly. Although some chemical SPFs provide broad-spectrum coverage, not all do, so be sure to read the label.

No matter what type of SPF you decide to use, neither will work if you aren’t applying enough or properly. According to the American Academy of Dermatology (AAD), you should be applying 1 oz, or a shot glass amount, to your exposed skin.

Summer is the time to make sure to reapply, since we’re sweating and more outdoors, but you should be applying sun protection every. Single. Day.

Featured image by Alexis Paige