A good bath. (I'm not joking)
His father told him that bathing causes many diseases - if you ever saw "My Fair Lady", Eliza wouldn't take a bath because she thought it was the cause of colds - or worse. In the movie "The Agony and the Ecstasy", Charlton Heston looked worse than a homeless person, even though Michelangelo was extremely wealthy when he died - equal to any Renaissance Era banker, i.e the Medici.
Of course he lived about double the normal life expectancy, so there may be something to this no-bathing thing. Just stay down wind of me. :-)