There are very few certainties in life, except for death, taxes, and the fact that you need to wear sunscreen every single day. Sun protection is up there with getting enough sleep, drinking enough water, and not setting yourself on fire with things that are absolutely essential for staying healthy — and beyond health, sun damage is one of the foremost causes of premature skin aging, so the need for SPF should appeal to your vain side, too.
But how does sunscreen work, and is wearing it really enough to protect yourself against the sun's most detrimental effects? The answers to these questions might seem obvious, but it's about time we clear it all up, just in case. Ahead, we demystify the specifics of SPF — and why it's so important that you wear it every day. (Have we mentioned that you need to wear it every day?)