Sunscreen vs. Sunblock: What's the Difference, and Which One Is Better?
If you take only one thing to the beach, it has to be sun protection. But when you stop by the drugstore to stock up and start reading product labels, you notice that there's two types: sunscreen and sunblock. What's the difference between the two, and is one better than the other? Health spoke to dermatologists to help us decode the fine print and unravel the benefits and drawbacks.
Sunscreen vs. sunblock: the basics
Sunscreen, which contains organic chemical compounds such as octyl methoxycinnamate, octyl salicylate, and ecamsule, relies on a chemical reaction to absorb UV light and convert it into heat, which is then released from the skin, London-based dermatologist Cristina Psomadakis tells Health.
On the other hand, sunblock contains mineral ingredients like titanium dioxide or zinc oxide that physically block UV rays. So the main difference in sunscreen and sunblock lies is the way they protect the skin from UV rays. Sunblock is so named because it literally blocks UV rays by forming a physical shield, while a sunscreen contains chemicals that absorb UV rays before your skin can.
Sunscreen and sunblock also have different application methods. Because sunscreen only works when it’s absorbed by the skin, it needs to be rubbed in. But you can simply slather sunblock on, since it acts as a physical barrier. You do have to apply sunblock evenly, though, since UV light can hit any exposed parts of the skin, no matter how small. Because sunblock isn’t rubbed in, it normally leaves a white cast on the skin, while sunscreen disappears completely.
Generally, sunscreens are designed to protect against UVA rays, which promote skin damage. Sunblocks, however, are formulated to stop the damage caused by UVB rays, the kind that cause a sunburn. But many sunscreens and sunblocks tick both boxes, helping to prevent wrinkles and sunburn.
Any side effects of sunscreen and sunblock?
If used correctly, the side effects of sunscreen should be minimal. It’s important to choose the right product for your skin type, particularly if you have sensitive skin. “Just as with anything applied to the skin, there is the chance of irritation or skin reaction,” Connecticut-based dermatologist Rhonda Q. Klein, MD, tells Health.
“Some sunscreens contain oil and can cause acne,” Deborah Jaliman, MD, a dermatologist in New York City, tells Health. “If you have very sensitive skin, others might sting or cause itching.”
Is sunscreen or sunblock better?
Both types of sun protection have their pros and cons, says Dr. Psomadakis. She recommends sunblock for people with sensitive skin or skin conditions, because some of the ingredients in chemical sunscreen might cause irritation or an allergic reaction. But ultimately, the best sun protection product is the one you like to use and works for your needs.
Dr. Klein gives sunblock the edge because it doesn’t have any chemical ingredients that can cause irritation. “Because physical sunscreens sit on the surface of the skin, they are well-tolerated by even the most sensitive skin types,” she explains.
All sunscreens and sunblocks come with an SPF (Sun Protection Factor). The American Academy of Dermatology advises using an SPF of at least 30, which blocks 97% of UVB rays. But remember, while higher SPF numbers block a little more of the sun's UVB rays, no sunscreen can block 100% of them.
What products do dermatologists recommend?
For a general sunblock for the body, Dr. Jaliman recommends Badger Unscented Sunscreen SPF 30 ($13.86; amazon.com). “It contains a very high (18.75%) concentration of zinc oxide, is water-resistant for 40 minutes, and is unscented, making it good for those with fragrance sensitivities,” she says. On top of that, it contains moisturizing sunflower oil and antioxidant vitamin E.
For sensitive skin, or skin prone to eczema or rosacea, Dr. Jaliman suggests EltaMD UV Physical Broad-Spectrum Sunscreen ($26.40; dermstore.com). “It has a high concentration of zinc oxide and titanium dioxide and offers both UVA and UVB protection,” she says.
Remember, sunscreen isn’t just for your body, and dermatologists recommend wearing it all year round—not only when the sun is out. (Clouds can block some UV rays, but not all) Dr. Klein’s favorites for everyday use on the face are ISDIN Eryfotona Actinica ($55.00; amazon.com) and EltaMD UV Pure Broad-Spectrum ($21.20; dermstore.com).
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