This is the most important thing to check (Image: Getty)
Summer is here, the sun is shining and with so many people heading outside to enjoy the weather it’s important to double check their sun protection. Most people already know to check the SPF number – but there’s a secondary marking on the back of bottles that people are urged to double-check.
Jessica Maxcy, skincare expert at Eight Saints Skincare, said: “Before using last summer’s sunscreen, find the open-jar symbol. It tells you how long the product should be kept after opening.” This symbol is often found on the back of makeup and skincare products and looks like a small open jar with a 6M, 12M or 24M marking on it. The ‘M’ means months and if it has been open for longer than what the ‘M’ indicates it should be disposed of.
What does it mean
It’s called the ‘Period After Opening’, or PAO, symbol, and Jessica says it’s one of the easiest details to miss when people reuse sunscreen from previous summers.
She said: “It’s a tiny symbol, but it tells you something incredibly important about the product.”
A sunscreen displaying “6M” should generally be used within six months of opening, while “12M” means 12 months and “24M” means 24 months.
The countdown begins when the product is first opened, not when it was purchased.
Jessica said: “Opening a bottle starts the clock. It doesn’t matter whether you’ve used half the bottle or only a few applications.”
The symbol is especially important for products like sunscreen, as if it has passed its PAO date it may no longer provide the same level of UV protection.
Jessica said: “Once a sunscreen is well beyond its recommended period after opening, it may become ineffective.
“That’s why checking the PAO symbol is so important, as it helps you avoid relying on SPF that no longer provides the protection you expect.”
Double check your sunscreen dates (Image: Getty)
Other signs to watch for
If your sunscreen has become runnier, lumpy, grainy or difficult to spread, it might have deteriorated. If anything seems amiss, it’s safest to dispose of it.
Jessica said: “A good sunscreen should feel smooth and consistent every time you use it. If it smells unusual, has separated or doesn’t look the way it originally did, I’d replace it rather than rely on it.”
Sunscreen should also be stored in a cool, dark place. Don’t keep it in the car, or on sunny windowsills as repeated exposure to heat can cause it to degrade.
Storage also matters. Sunscreen is often left in hot cars, on sunny windowsills, or inside beach bags, where repeated exposure to heat can gradually affect the formula.
Rather than trying to revive an old bottle by adding moisturiser or water, Jessica recommends replacing any sunscreen you’re unsure about.
Jessica added: “It’s a small expense compared with spending time outdoors using SPF that may no longer perform as intended.”
This story originally appeared on Express.co.uk
