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Olivia Harvey
June 29, 2018 8:08 am

Summer is officially in full swing and we’re ready to morph into our true beach bum selves. But before we do so, it’s vital to lather on the sunscreen before soaking in those summer rays. And what’s even more vital than applying is checking the expiration date on your favorite bottle of sun protection. That’s right — sunscreen, like all cosmetics, expires, and there’s a tiny secret symbol that tells you how long the ingredients in your sunscreen will remain active.

Depending on the brand, there are a few different ways you can locate a sunscreen’s expiration date. According to TheSun.co.uk, some sunscreen brands depict a little open jar on the back of the bottle. The open jar icon is usually accompanied with a number such as “12M” or “18M.” This number tells you how many months the sunscreen will stay effective after opening — so, 12M stands for 12 months.

If you can’t find the jar icon, or any form of expiration date markings, this means your sunscreen is most likely formulated to last three years after you open it, says the Mayo Clinic. Help yourself out and write the date of purchase on all your sunscreens to make sure you know when it’s time to chuck them.

Another obvious sign that your sunscreen is no longer good is a color or consistency change in the formula. Lumps, yellowing, and liquid separation are all signs that it’s time to buy new sunscreen, whether expired or not.

After purchasing a sunscreen, do your research to make sure you know how a brand labels their product. For example, Banana Boat brand sunscreens use a different method than the jar icon to label expiration dates.

Their packaging comes with a code that might appear like, “15090CF,” which marks when the sunscreen was created. The first two numbers in the code mark the creation year (“15” stands for 2015), and the next three numbers mark the day within the year the sunscreen was made (“090” stands for the 90th day in the year, which is March 31st). According to their website, Banana Boat sunscreens are formulated to last three years, so you can use the code to count backwards to see how long you’ve owned the bottle.

Expired sunscreens are ineffective and will not protect your skin from harmful UV rays. When in doubt, do yourself a favor and buy a new bottle to avoid the dreaded burn.

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