5 Tips for a Healthy Tan

1. That bright sky ball is emitting more than one kind of noxious ultraviolet radiation: UVA and UVB. “Essentially, all sunburn is caused by UVB radiation,” says Bookout. Think B for burn—but UVA ain’t no angel. It can induce redness with certain meds and cause DNA damage. “Both UVA and UVB play important roles in skin cancer development and aging skin,” Bookout explains.

2. SPF (i.e., “sun protection factor”) is not the whole story—measuring only how well the sunscreen protects against UVB (aka sunburn). “UVA protection is not accounted for in the SPF label,” Bookout says. But you can still suit up against those harmful rays by arming yourself with a broad-spectrum ’screen, meaning it protects you from both.

3. Application matters—and for sun protection, there’s a method to the madness. “Most [people] inadequately apply sunscreen,” says Bookout, using “too thin of a layer, [which] decreases the SPF to about half the number on the label.” In addition to administering an adequate amount, she recommends “applying sunscreen 20 minutes prior to sun exposure and again 30 minutes after sun exposure has begun.”

4. Beyond the UVA/UVB reality, active sunscreen ingredients actually fall into two categories: chemical and physical. Chemical active ingredients absorb UV radiation, while physical sunscreen agents scatter or reflect UV radiation away from the skin. “Most sunscreens contain both chemical and physical agents,” says Bookout. “While there are many chemical agents, the only physical sunscreen agents are titanium and zinc.” Before choosing, consider pros and cons—skin type, allergic reactions, your activity level, etc. (Note: Physical sunscreens are naturally broad-spectrum.)

5. Be picky. Doc’s pref? “Medical-grade sunscreens or those carried by dermatologists due to their higher standards of production,” says Bookout, who gave us the insider scoop on a handful of her faves (see sidebar). But, she says, if you’re in a pinch, turn to drugstore brands Neutrogena, Aveeno or La Roche-Posay for their favorable sunscreen stability.

Source: Angela L. Bookout, DO, FAOCD, board-certified dermatologist, SIA Boutique Dermatology, @siadermatology