This won’t lead to people using less lotion, but it will lead to fancy lotions adding “OH precursors” as the new science buzzmarketing term
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Buddy of mine did research in Milan on common sunscreen ingredients. In a lab, those chemicals didn't tend to cross the dermis.
But put that person in the sun and you find detectable quantities of those chemicals in serum within minutes. Turns out the flushing (i.e. rushing of blood to the skin, in particular, to the surface of the dermis) increases permeability. Nobody really tested those chemicals for intravenous use.
So in a very real sense, you ingest in all but digestion the ingredients in your lotions.