It's always hot hot hot here in the Middle East, which means you should be carrying your sunscreen around with you everywhere you go, almost as religiously as you do your phone. But here's a pop quiz question: what does the SPF number of sunscreen actually mean?
I mean, obviously you know SPF stands for 'sun protection factor', but up until recently I bet you were none-the-wiser on what the 15, 30, 50 and so on really represented. As far as I was concerned, they were just a random numerical scale much like tennis scoring, with the higher numbers only generally indicating a heavier level of coverage.
But it turns out this is not the truth. There is in fact a rational reason why the SPF numbers are what they are: they indicate how many multiples of time you're safe to be out in the sun before you burn.
The Skin Cancer Foundation describes it like this:
"If it takes 20 minutes for your unprotected skin to start turning red, using an SPF 15 sunscreen theoretically prevents reddening 15 times longer — about five hours."
And it makes total sense. SPF 15 will give you 15 times the number of minutes before you burn than you'd have with no sunscreen protection at all. I know people overuse this phrase in the world of online journalism but really, it feels relevant for me now: mind, blown.
Sincere apologies if you've known this your whole life and I'm here looking absolutely silly because I wasn't aware, but I'm one of at least 3 people currently surrounding me who also didn't know, so it would've been wrong not to share the knowledge.
H/T Cosmo UK