What's the Difference Between Sunscreen and Sunblock, Anyway?

Off to the pool? We asked a dermatologist and a chemist which is your best option for preventing burns.

What's the Difference Between Sunscreen and Sunblock, Anyway?

Sunscreen vs. sunblock is arguably the least heated debate ever—most of us grab whatever’s on the shelf, slap it on and, so long as we’re not a luminous pink when the sun sets, we’re happy. We should care, though: The sun protection we use today will keep us from looking like a wrinkled raisin-person later in life. So with that in mind, is one form of sun protection really better than the other? We asked dermatologist Anthony Rossi and product wiz Fadi Mourad which is best as far as sunscreen vs. sunblock goes.

Sunscreen: How it Works

Let’s start by looking at what’s in each of these products, and how they work. First up: Sunscreen. “A sunscreen is a chemical compound that absorbs and attenuates UV wavelengths that would otherwise interact with and affect the skin,” Rossi explains. In simpler terms, sunscreen acts sort of like a window shade, reducing (but not completely blocking) the effects of the sun’s harmful rays. They usually contain organic compounds called benzophenones, which protect against UVA radiation (the kind that causes premature skin aging and wrinkling), and cinnamates and salicylates, which protect against UVB radiation (the kind that causes sunburns and melanoma skin cancer). Rossi highly encourages the use of sunscreens that are labeled “broad-spectrum,” which protect against both UVA and UVB radiation.

Sunblock: How it Works

“Sunblock, on the other hand, physically reflects the sun’s rays, preventing them from penetrating the skin,” Mourad explains, which is why they technically provide more sun protection than sunscreen does. Sunblocks typically contain protective ingredients like titanium dioxide and zinc oxide, according to Rossi, which tend to appear white on the skin. Because titanium dioxide and zinc oxide are less irritating than the ingredients found in sunscreen, sunblock is usually the better choice for those with sensitive skin.

Sunblock vs. Sunscreen: The Experts Weigh In

Now that we understand how both forms of sun protection work, here’s what our experts have to say when it comes to sunblock vs. sunscreen: “Sunscreen and sunblock are both excellent forms of sun protection,” Fadi explains. “You’re good to go as long as the one you choose protects against both UVA and UVB rays and is water-resistant or sweat-resistant [be sure to check the number on the container that indicates how long the sunscreen remains effective while swimming or sweating].”

So there you have it: Sunblock is the better option for those with especially sensitive skin, but otherwise, you are free to go on obliviously lathering up with either in the name of keeping your skin burn-and-wrinkle-free, provided that whichever you use, you’re using it correctly. Either way, Rossi emphasizes what’s more important is that the product you choose has an SPF of at least 15 and that you reapply it liberally every two hours spent under the sun (and after every dip in the pool). As long as you can manage that, your skin will look and feel healthy as ever.

If you’ve already been burned because you didn’t even bother to consider the whole sunscreen vs. sunblock thing, soothe your skin with our dermatologist-approved remedies—and avoid pats on the back as best as possible.