Image via Laura Mercier

Thank christ the weather is getting warmer, and I don't know about you, but my pasty ass has definitely been spending a little more time outside lately. This brings us to a particularly Product Fiend-esque dilemma: How much sunscreen is enough?

Since many of us have switched to foundations and powder that contain the tag line, "SPF 15," it seems acceptable enough to eschew another layer of sunscreen since, what the hell, aren't one or two layers of sunscreen enough?

The short answer is: no.

A dermatologist that I've always enjoyed interviewing, Dr. Leslie Baumann, breaks down the longer answer like this:

When scientists test facial powders to determine SPF (as mandated by the FDA), they typically assume that 2mg of product will be used per cm² of skin. The average face is about 600cm² (although that varies from person to person, of course), meaning that a person needs to apply about 1.2g of facial powder to get the SPF stated on the product's label.

 

So what's the problem? Studies show that most women only apply about 0.085g of powder at a time. In a nutshell, you'd have to apply 14 times the amount of powder you usually do to be sufficiently protected against the sun! Even if you were willing to cake on your makeup, there's no way to pile on that much powder. Bottom line: While it's never bad to use products with SPF, your facial powder is simply not offering enough protection against UV waves to use it in lieu of sunscreen. 

So, what's a UV-sensitive gal to do? Go ahead and layer up, and layer some more. Before you go out in the sun, spread on an ample amount of old-fashioned sunscreen (Le Roche-Posay Anthelios XL Lait is definitely where it's at). After you've given it a chance to set (about five minutes), apply a foundation or tinted moisturizer that also  contains sunscreen, and don't be shy about dusting on an SPF-enriched powder like Laura Mercier Mineral Powder SPF 15.

Okay, you can go now.