Sunscreen Question

Summer’s finally arrived here, and I’ve got a sunscreen question.

My facial moisturizer has an SPF of 15.
My bronzer has an SPF of 15.
My foundation has an SPF of 10.

I always buy moisturizer with suncreen, but the bronzer and foundation just happened to come with it. I apply them in that order - lotion, bronzer, foundation.

Now, I’m wondering if I get any extra sun protection from the three products. It was my impression that for sunscreen to work, it had to be touching the skin. So is it just the SPF of the moisturizer that has an effect? Thanks Dopers!

Hi amaranta. Any chance this is you?

:smiley: Bump…

If you’re like the majority of people, there’s not a sufficient layer of any of those products to yield the labeled SPF, much less their sum. SPFs are measured using a standard amount of product that exceeds what most people find comfortable on their skin. Putting all three on might be pushing you up to, or even beyond, 15, but it’s unlikely that you’re much beyond that.

And no, sunscreen doesn’t need to touch the skin, it just needs to be between you and the sun. The proper application is a thick layer that will leave you feeling greasy for a while. Spreading it out thin so it’s not greasy reduces the protection.

Nametag is right: generally, makeup with sun protection would have to be applied Joan Rivers thick in order to provide the labeled protection (assuming it even provides full-spectrum UV protection, which the number doesn’t tell you.) Using them all together might add up to enough for SPF 15, but my understanding is that when you use multiple products together, the SPFs aren’t additive.

I was always told you should apply sunscreen 15-20 minutes before venturing out into the sun to let it be absobed into the skin. This would seem to imply that it’s not the layering of the product at all that does the work. Is sun screen protection different from the SPF protection of makeup?

There are two kinds of sunscreen: physical and chemical sunscreens.

Chemical sunscreens work in a way I don’t quite understand even though I saw a thing on the History channel about them only yesterday. Physical blockers form a phsyical barrier to the sun, like zinc oxide. However, physical blockers are not absorbed into the skin - they form a barrier on the surface. Makeup probably contains an element of phsycal blocking and an element of chemical blocking.

Did you know a white cotton t-shirt only has an SPF of 6?