Does Sunscreen Expire?

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It's time to head to the pool, but the only sunscreen you can find is the half-used tube at the bottom of last summer's beach tote. Will it still protect you? 

Maybe.

Sunscreen is formulated to remain effective for at least three years, according to Food and Drug Administration regulations- but not forever. Check the expirartion date on the container and toss it if it has passed. If there's no date on the tube and you can't remember when you brought it, play it safe and buy a new one. Write the purchase date on the new container with a permanent marker. Remember, too, that even on the new bottle of sunscreen, heat can accelerate its breakdown, so avoid storing it in places where the temperature can spike, such as in your car. The FDA also recommends that you keep sunscreen out of direct sunlight by swaddling it in a towl or stashing it in the shade or even in a cooler when you carry it with you on outings.

Helpful tips:

• Reapply every 2 hours or after swimming or sweating.
• "Water-resistant" sunscreen must maintain their SPF level for either 40 or 80 minutes of swimming or sweating.
• Use a sunscreen with an SPF of 40 or higher and cautious of mineral formulations, which we found to be less effective. 
• Wearing a swim shirt in the water helps protect your skin-and potentially the enviroment because less sunscreen is applied. 
• No matter what your skin type the sun can cause damage. 

Consumer Reports, Issue July 2018