Well, if that last point stumped you, you’ve come to the right place. Let us explain the world of mineral and chemical sunscreens, how they work, and the various pros and cons. “Zinc oxide is a mineral that reflects light, including longer wavelength UVA, from the skin’s surface,” says board-certified dermatologist Loretta Ciraldo, M.D., FAAD. “It is one of only two mineral (also referred to as “non-chemical” or “inorganic”) sunscreen active ingredients, but it is the only one that is effective at blocking UVA since titanium dioxide doesn’t effectively block UVA.” But as author and chemist George Zaidan explains, mineral sunscreens also do some absorbing—like like their chemical counterparts. Essentially, they work in two ways: First by blocking some rays, and second by absorbing the rays and deflecting their damage by turning it into heat. For the non-nano part, be weary of micronized zinc as these are able to be ingested by marine life, and potentially causing harm. Many brands are, we should note, getting better at masking the white cast and making it blend in easier. So it may take some testing around, but you may just find the right option for you. (We also did the work and found options for any skin tone that you can check out here.) Experts agree: “Try to avoid the sunscreen ingredients oxybenzone and octinoxate. They are significant skin allergens and have been shown to have some estrogen-mimicking effects on the body2,” physician Sarah Villafranco, M.D., writes about ingredients to avoid. However, given the absorption and environmental concerns around chemical sunscreens, we suggest opting for mineral. Sure, there aren’t as many, may be harder to rub in, and some options are pretty thick, but their safety profile (both for skin and the environment) makes them the best bet. And formulas are only getting more sophisticated with time: In fact, you can find more than a few solid options on the market, with emollients and tints to help with spreadability and wear. However, if your favorite sunscreen is a chemical number, we’d rather you wear that than nothing at all. We should caveat: It’s also OK to have a sunscreen wardrobe. Let’s say you want a sheer face lotion for day-to-day (understandable), that doesn’t mean you can’t also have a mineral body option to slather on when you’re at the beach. This isn’t an all-or-nothing scenario.