Lauren Conrad knows a lot of things (how to make rose cupcakes, for instance) and one area she seems very up-to-speed on is her sunscreen facts. In her new column over on Refinery29, she goes into when to wear it (pretty much always), the SPF number to look for (30), and she gives a really useful reminder when it comes to layering sunscreen.
She writes, "The SPF number is simply a standard for how long you can tolerate the sun without burning. So, if you can stay in the sun for 10 minutes without burning, an SPF of 15 would allow you to spend 150 minutes in the sun before burning... . For those of you who think that layering on SPF 15 over your SPF 10 will give the protection of SPF 25, think again. Layering does not increase the SPF. I suppose the only benefit is that it ensures that every area is covered."
In other words, go for an SPF of 30 (which derms generally advise anyway) instead of two layers of 15. You'll save yourself some cream—and the pain of an accidental sunburn.
Head on over to her essay to read more of her tips. You guys surprised by know much she knows?