Sunscreen 101

Find out how to decode sunscreen so you can have more fun in the sun— and stay protected.

SPF (Sun Protection Factor)

This indicates how much of the sun’s UV radiation is absorbed by the sunscreen. For example, SPF 30 means the sunscreen reduces the sun’s burning radiation reaching your skin by about 97%. In other words, it allows only a tiny fraction (1/30th) of UV rays to penetrate.

Broadspectrum vs. UVB or UVA Protection

Sunscreens should provide protection against both UVB and UVA rays. UVB rays cause sunburns, while UVA rays penetrate deeper into the skin and can contribute to aging and cancer. Broadspectrum sunscreen protects against both UVB and UVA rays.

Water Resistant

Sunscreens labeled as “water resistant” maintain their SPF protection for a period of time while swimming or sweating. Labels will often indicate 40 or 80 minutes of water resistance.

Reef-safe

Reef-safe sunscreens are mineral based (most commonly using titanium dioxide or zinc oxide) as opposed to chemical based. Typically, it refers to sunscreens that don’t contain oxybenzone or octinoxate, which have been linked to coral bleaching. However, this claim is unregulated.

Apply sunscreen 15–30 minutes before going outside to allow it to fully absorb.

One ounce of sunscreen (roughly a full shot glass) is recommended to fully cover the body and get full SPF efficacy.

Reapply every 2 hours, or more frequently if swimming or sweating.

Opt for an SPF of 30 or higher for the best protection.

Don’t forget often-missed spots like lips, ears, around the eyes and the scalp if you have thin hair.