The role of zinc oxide in skin care is to function as a physical sunscreen. What that means is zinc oxide is able to physically block UVA and UVB rays from reaching the skin, protecting it from the harmful effects of too many UV rays on the skin.
Zinc oxide is one of the best sunscreen filters that we can use in skin care to shield our skin from the sun. However, there’s one drawback - zinc oxide can leave a pretty strong white cast, aka the weird effect of making your skin look whiter or paler after applying a sunscreen with zinc oxide.
To reduce this effect (as it makes you less likely to want to wear SPF!) many sunscreens use the benefits of zinc oxide with ingredients called chemical sunscreens to ensure broad-spectrum, effective protection from the effects of the skin.