UV, aka ultraviolet light, is an undetectable and invisible radiation. It most commonly comes from the sun, but it’s also present in tanning beds and other devices.

The sun is of course the most significant form of UV radiation. Learn more about UVA and UVB here.

It’s a common misconception that UV is only present when the sun is visible. Spoiler alert: all forms of UV light are still present in the atmosphere, no matter the weather forecast.

SPF isn’t something you should save for sunny holidays – it’s just as important to protect your skin on a cloudy day at home!