While at Walgreen's this evening perusing the Neutrogena US DryTouch
sunblocks, I noticed SPF45 and SPF30. The only difference touted on the
label of the two products is that the SPF30 contains Parsol 1789 and the
SPF45 does not say that it does. The active ingredients on both labels were
the same in slightly varying percentages, with the higher SPF containing the
higher percentages, of course. Why then, the Parsol 1789? I know it's a
form of sunblock, but why is it in the lower of the two SPF's? Does this
make it any more effective than the higher SPF formula? Is this a chemical
block? What is a physical block? Avobenzone? If so, they both have it.
I'm confused.
I bought the higher SPF.
Thanks.
Jamie