Quick reminder: yes, sunscreen does expire, and you definitely shouldn’t use old sunscreen. Here’s what you need to know.
How old is my sunscreen, and how long is sunscreen good for?
Nearly all over the world, two rules of thumb are a good guideline: your bottle will either have a clear sign that shows you how long you can use your sunscreen ONCE THAT YOU’VE opened it, or it’s good for three years – if it doesn’t say otherwise on a bottle. (Full disclosure, I haven’t found many sunscreens that don’t come with a 12m expiry date.)
When does sunscreen expire?
Honestly, use common sense when carrying your SPF with you. Don’t leave it in a car, or in the sun at the pool. Your bottle or tube shouldn’t overheat. Don’t let it be lying around with the cap off.
Both heat and oxygen can degrade a formula, no matter if you’ve got a physical or chemical filters. (Light also is a big culprit: run for the hills if you see an SPF packaged in a jar, or see-through bottle.) The particles that absorb and deflect rays in physical sunscreens tend to clump together over time, while in chemical sunscreens, not only the active ingredients might degrade: also ingredients that stabilize filters and aid with absorption might degrade.
Does expired sunscreen work?
Here’s the thing: nobody really knows. The SPF50 from your beach bag last year that you just unearthed from the back of your cabinet because you’re going on Spring Break: it’s possible that it has still protective faculties of an SPF25. Or, maybe, it’s an SPF5 now.
With sunscreen, though, that matters: you depend on it for skin cancer prevention, especially if we’re talking about a “vacation sunscreen”: the one you’re going to use when you’re out about on the beach, at a pool, hiking in the mountains.
Your chance of burning up and maximizing your risk for skin cancer will be much higher if you don’t know what protection you’re getting.
(I don’t want to minimize the risk of using expired SPF when you’re just out and about, running errands: but I feel on a vacation it’s exponentially higher.)
What you shouldn’t worry about:
– That Octocrylene in your sunscreen turns to benzophenone and will give you cancer. Michelle from Labmuffin debunked that one really well. (Tl,dr: the researchers who came up with that one last year are affiliated with cosmetics company Pierre Fabre who were launching a new Octocrylene-free SPF. *eyeroll* Anyways, the amounts of benzophenone in your sunscreen are likely to be three times lower than the amount you can safely DIGEST. The end.)
