• Zinc oxide is a common skin-care ingredient [1] in mineral-based sunscreens.
• Zinc oxide protects from both UVA and UVB rays.
• Mineral sunscreens [2] repel sunlight by sitting on top of skin, creating a physical barrier.

We're officially in the dog days of summer, which means sunscreen is more important than ever [3] as we start to spend more time in the sun. Don't forget: exposure to the sun's rays can be damaging to our skin. Thankfully, sunscreen comes to our rescue, shielding skin from the detrimental effects. And zinc oxide, a common ingredient in many sunscreen formulas [4], has long been known for its protective abilities.

Ahead, get the scoop on how zinc oxide works in sunscreen, get product recommendations [5], and learn what else the ingredient can do.

What Is Zinc Oxide?

Zinc oxide is a mineral that's white in color and has a powdery consistency when on its own. When added to sunscreen formulas, like its cousin titanium dioxide [6], zinc oxide acts as a physical blocker that sits on top of skin to shield it. This is why it's called a physical (or mineral) sunscreen, as opposed to a chemical sunscreen [7] (which use ingredients like oxybenzone and avobenzone [8]), which get absorbed into the skin to repel the sun's UV rays.

Zinc oxide is known to offer more broad-spectrum protection than titanium dioxide, meaning it has you covered blocking both UVA (responsible for skin aging) and UVB (causes sunburn and inflammation) rays. Mineral sunscreens [9] with zinc oxide are often a top choice for those with skin issues like eczema, as they aren't known to be irritating to skin. They're also a preferable pick for babies and children because they won't penetrate their delicate skin or disrupt hormonal activity.

Is There a Downside to Using Zinc Oxide?

Zinc oxide is touted as a safe pick by the FDA and dermatologists alike. One drawback is that zinc-oxide formulas often don't disappear easily into skin, leaving a white cast. Look for formulas that are on the sheer side like the Doctor Babor Protect RX Mineral Sunscreen SPF 30 [10] ($49) or the Summer Fridays Shade Drops SPF 30 [11] ($36). A tinted version like the Cotz Flawless Complexion SPF 50 [12] ($28) is another good option that may blend better into dark skin tones.

What Else Is Zinc Oxide Used For?

Zinc oxide is also used in diaper-rash creams like the Pipette Diaper Rash Cream [13] ($11) and burn salves. How does it manage to be so multipurpose? "Just as zinc oxide acts as a shield or barrier to UV rays, it works the same way for irritation from diapers and can even help seal in moisture and heal wounds and burns," says board-certified dermatologist Roberta Del Campo, MD, a medical adviser to Babor Skincare.