This is how to tell if your sun cream has expired
Because that bottle of old sunscreen might not be protecting your skin!
Picture this: It's the day before your summer holiday, you've semi-packed (aka, emptied the entire contents of your wardrobe onto the bed), and then it hits you: The all-important sun cream is missing. Your face SPF is with you year-round, but one for your body? Nowhere to be seen… Last year's holiday left you with a ton of half-used bottles, and now, they're hidden away in that cupboard under your bathroom sink. The question is, are they still safe to use?
To find out – once and for all – what's the deal with sun cream going bad, we hit up cosmetic dermatologist, Dr Mervyn Patterson from Woodford Medical. Plus, we get answers on how long sunscreens last, plus how to know if it's expired?
Let's go back to the basics...
Does sunscreen expire?
"Most sunscreens do expire, and because of this, a lot should come with an expiry date stamped on the box," explained Dr Patterson. "It is very important not to ignore this as the chemicals do degrade and may well lose their protective effect."
That's all well and good, but what if you've thrown away the box - and with it - the expiration date? As a rule of thumb, Dr Patterson says most sun tan lotions will last for "at least a year of use".
Signs your screen has expired
The warning signs to look for are smell and texture. If your sun protection has expired, the formula will have started to separate; "If it's looking different in terms of texture or smell from when you first bought it, then things may not be well with the product. In this case, it's best to simply discard."
But what happens if you accidentally use expired sun cream? In short, it's pretty likely you'll burn in the sun, and the formula itself could trigger a reaction from your skin; "If a sunscreen product has deteriorated, then in theory there is a risk of chemical alteration of the ingredients." This means that there's a greater likelihood of “contact reactions” with the skin and it could be irritating. There will also be a decrease in sun protection, hence the burning. Ouch.
What causes sunscreen to expire?
Most sun creams have been designed to withstand a lot, "however, if the containers are left in direct sunlight, even the most stable of formulations can degrade." Dr Patterson continues, "Storage is important. Leaving your sunscreen baking in the sun, whether it's on the beach or in the back window of your car, may trigger degradation of the formula, and that renders the product useless." The best place to store it? Somewhere shaded, preferably cool and dry.
So now we know what to do (and what not to do) to give our SPF the longest life possible... Just remember, if in doubt, chuck the old stuff and pick up a new bottle - we know sun cream can be pretty pricey, but it's worth protecting your skin no matter what.
Some of our fave body SPFs...
Credit: Cosmopolitan