For some bizarre reason, most people do not realise that their sunscreen has an expiry date. The problem with this is that expired sunscreen will not protect you from harmful UVA and UVB rays and using it without realising you are not protected is a sure way of increasing your risk of skin cancer or at the very least, going home with a painful sunburn.

Wearing sunscreen every day, especially if you’re outdoors, can help prevent premature skin ageing, pigmentation, sunburn, and even skin cancer. Skin cancer affects over 3.3 million people each year, according to an article in the Journal of the American Medical Association, so taking the time to apply sunscreen every day is crucial, and it helps to ensure that the sunscreen that you are using has not passed its expiration date.

Any product that is not marked or stamped with an explicit expiration date is required by the FDA to be stable for at least three years. This means that you can use leftover sunscreen from one year to the next. Some sunscreens include an expiration date, so be sure to read the packaging.

Most sunscreens are clearly stamped, embossed, or stickered with an explicit expiration date and should not be used after expiration.

To make sure that your sunscreen remains effective once opened, the FDA suggests keeping it away from direct sun or heat. If you’re outside for extended periods of time, cover your sunscreen in a towel or keep it away from the sun. The efficacy of your sunscreen halves every two-four hours, so it’s important to reapply, especially if you are outdoors.