We should all be using sunscreen, but when it comes down to picking one, there's no key to the language on the bottle, and SPF isn't the only thing to look for. Here's a guide to the other biggies: UVA, UVB, and "broad spectrum."
Image by Sweet Carolina Photography.
Most of us probably base our decision to choose one sunscreen over another on SPF, or "Sun Protection Factor" which is an estimate of how effectively sunscreen can reduce the time to sunburn. That's fine, because the American Academy of Dermatology recommends SPF 30. SPF 15 is the absolute minimum, but beyond 15 the differences in sun protection become less and less significant.
Other terms you'll find on a typical sunscreen bottle typically include "UVB", "UVA", and "broad spectrum", which all have to do with ultraviolet radiation (UV) from the sun:
- Ultraviolet A, or UVA: Known as "ageing rays", UVA can get deep into your skin and increase the chance of skin ageing, like getting wrinkles and sunspots. It can pass through windows.
- Ultraviolet B, or UVB: Known as "burning rays", UVB is primarily responsible for sunburns. It can't pass through windows.
- Broad spectrum: If included on the label, the sunscreen is designed to protect against both UVA and UVB, which means that when you use it (in addition to other sun-protective protocols) you protect against sunburn and reduce the risk of skin cancer and skin ageing. If this is not labelled, the sunscreen merely helps prevent sunburn.
Water resistant sunscreens mean the protection lasts between 40 and 80 minutes while you're in the water -- the bottles should be clear. Whatever you buy, make sure you apply the recommended amount in the first place.