Round Lab sunscreen review: what to check

What should the label tell you?

SPF mainly describes protection against UVB, the rays responsible for sunburn. Broad spectrum means protection against both UVA and UVB. UVA also contributes to skin ageing and pigmentation, so an SPF number alone is not the whole decision. Water resistance is a separate feature to look for, not something to infer from a high SPF.13

What are the ingredients in Round Lab sunscreen?

Use the ingredient list on the exact product to identify its sunscreen filters. Sunscreens often combine filters to cover different parts of the UV spectrum. Ingredients such as avobenzone, octocrylene and bemotrizinol are chemical filters; zinc oxide and titanium dioxide are mineral filters. These are examples for reading a label, not an ingredient list for Round Lab.3

Is Round Lab sunscreen a physical sunscreen?

That depends on the filters in the exact formula. Physical, or mineral, sunscreens commonly use zinc oxide or titanium dioxide. Chemical filters absorb UV radiation, but mineral filters also protect mainly through absorption rather than simply bouncing sunlight away.3

How should you apply it?

1. 1Apply sunscreen about 15 minutes before going outdoors.
2. 2Use at least one teaspoon for your face and rub it in thoroughly. Cover other exposed areas, including your neck and ears.
3. 3For exposed body skin, most adults need at least one ounce, roughly a shot glass, with more needed depending on body size.
4. 4Reapply every two hours outdoors and immediately after swimming or sweating. Cloudy weather and winter do not remove the need for protection.

How does a sunscreen stick differ?

Sticks can be convenient around the eyes and on the backs of the hands, so the applicator has a job beyond looking tidy. General guidance for stick sunscreen is four passes back and forth over each area, followed by rubbing it in for even coverage. Still check for SPF 30 or higher, broad spectrum protection and water resistance.2