These creams have some chemical that blocks the UV with some capacity, say a factor of 50. Why can’t I apply two layers of this cream to now get a 100 factor equivalent protection?
I asked the chemist at the store and they said it’s not how it works and that the highest protection factor they have is 75 (which was super expensive).
What gives?
Edit: Thank you for those super informative answers.
I just looked it up and America will soon get the good sunscreens. Bemotrizinol has just been FDA approved.
Until then, I am sticking with American has some bad sunscreens. Until I guess this month.