Chemical vs. Physical: Which Sunscreen Should You Use?

Navigating the sun protection aisle at the drugstore seems to become a more daunting task every year. And it’s also more important than ever that you get adequate sun protection—according to the Skin Cancer Foundation, skin cancers are now more prevalent than ever, afflicting one in five Americans. And about 90 percent of the time, the risk of developing skin cancer is directly related to the amount and intensity of ultraviolet light we’re exposed to.

Not sure how to choose from the options on the shelves? Start with the basics: choosing between chemical and physical sunscreens.

Chemical Sunscreen

The lowdown:

Chemical sunscreen (also called organic sunscreen) contains carbon compounds such as oxybenzone and octinoxate that absorb UV rays and release the extra energy as heat. For both UVA and UVB protection, look for “broad spectrum” on the label—UVA rays penetrate the skin more deeply, even though it’s primarily UVB rays that cause sunburn, so protection from both is a must. 

What to keep in mind:

Plan ahead—chemical sunscreen takes about 20 minutes to fully sink in. And don’t skimp when you apply (and reapply). The SPF is only accurate if you’re applying the amount recommended on the bottle. If you’re using a spray-on formula, don’t use it on your face or on your kids, Consumer Reports cautions—spray sunscreens may be more convenient than rubbing in lotion, but safety experts have concerns about breathing in the ingredients.

If you have sensitive skin, pay attention to how you react to chemical sunscreens—and make sure you check your makeup bag for skincare and makeup products with SPF. “Chemical sunscreens tend to be more sheer and less reflective than physical sunscreen and are formulated into many facial moisturizers and lip products with SPF,” says Dr. S. Manjula Jegasothy, founder of Miami Skin Institute. “Because it penetrates the skin, some people may be sensitive towards chemical sunscreen.” Check the label and look for keywords like oil-free non-comedogenic (won’t clog pores).

Physical Sunscreen

The lowdown:

Physical sunscreen is also called ‘sunblock’ because it uses active mineral ingredients like zinc oxide or titanium dioxide to physically block UV rays—it doesn’t absorb them like a chemical sunscreen does. You’ll sometimes see it in the drugstore aisle as “mineral” or “natural” sunscreen, too.

What to keep in mind:

Unlike chemical sunscreens, which need time to absorb, physical ones start working immediately, so they’re a great option if you arrive at the beach and realize you didn’t apply beforehand. That said, physical sunblock formulas tend to be thicker, so they sometimes require a little elbow grease to rub in. Just keep an eye on it, says Dr. Sonita Sadio, founder of Sub Rosa Private Aesthetics. “While it does protect once applied, it can be rubbed off easily despite its thickness.”

Got finicky skin? Physical sunscreens are likely to be a better option for you than chemical sunscreens. “As they don’t absorb into the skin, they’re suitable for all skin types, even sensitive skin,” says Dr. Jegasothy.

The white sheen of physical sunscreen may turn you off, but Dr. Jegasothy says she recommends them because they provide better UV protection. “If the white sheen of physical sunscreens bother you cosmetically, opt for a chemical sunscreen when you have a glamorous outdoors event like a wedding,” she says.

Whichever you choose, don’t let your bottles of sunscreen, physical or chemical, migrate to the back of your medicine cabinet come September. “Don’t let your sunscreen become a fair-weather friend,” says Dr. Sadio. “From the hottest day to the coldest day of the year, one must apply sunscreen! The sun might not seem to appear, but it’s there. The sun’s UV rays are still passing through clouds and individuals are unknowingly exposing their skin to those rays.”