Sunblock or Sunscreen Which Do You Want
So back to SPF, what exactly are you getting. Well, first of all there is no known UVA rating for protection. No SPF grading system is for UVA. So all of the grading is for UVB. And the ratings are for "amount of time, relatively, it takes you to burn.." A very general term. So if you normally burn in 10 minutes and you are wearing SPF 30, you should be able to stay in the sun for 300 minutes before you burn. But that doesn't mean that you haven't absorbed a lot of heat during that time, nor that the product has stayed on that long, nor does it really mean that you really took that long to burn in the first place. Nor does an alarm sound when you have incomplete or inconsistent application, are at altitude, or exposed to conditions like wind, or taking medication that can compound the effects of the sun. Nor do these figures correct for age or ethnicity, that's basically up to us, so these products have a lot to be desired in their labeling. .And the concern over the lack of UVA protection was so great that last July 3, 2009 caused a lot of alarm when they reported that three of five brand-name products "either don't protect the skin from sun damage sufficiently, contain hazardous chemicals, or both, according to a report by the watchdog organization Environmental Working Group."
And if you want to see just how smart you really are about this:
How about the sun safety IQ
Colorescience and SkinSceuticals from Hada! Find out about he concept of cellular sunscreen. And come in for your skin checks yearly!