She probably means the Neutrogena is chemical protection so it soaks into the skin. The Vichy is titanium dioxide so it sits on top of the skin. I liked Biotherm though its part chemical and TD and it worked really well even though I didnt get a chance to reapply. It does smell too strong of citrus though but its not as greasy as Vichy. Anytime you use high SPF and titanium in it, it will be more greasy.