
You’ve just claimed a spot on the beach; the sun is rising overhead, and you’re looking forward to a relaxing day of sea and sun.
And speaking of sun — you mustn’t forget to apply a generous layer of protective sunblock. But when you reach for your tube of sunscreen, you notice that it’s long past the stamped expiration date.
Should you use it anyway?
Sunscreens typically provide protection with active ingredients that absorb or reflect ultraviolet (UV) radiation, such as zinc oxide or titanium dioxide, and so-called “broad spectrum” products block out two types of potentially damaging UV radiation — UVA and UVB rays, the Melanoma Research Foundation reported.
Most sunscreens will remain effective up to three years after the container is opened — unless the brand’s expiration date says otherwise, according to the Mayo Clinic. However, storage in hot places or exposure to moisture can break down a sunscreen’s components and reduce its effectiveness even before it’s “officially” expired, Dr. Lauren Ploch, a dermatologist, told Live Science in an email.