Why does French say “je me brosse les dents”?

French normally keeps possessives off your own body. You say je me brosse les dents, literally “I brush to myself the teeth.” The little me already says whose teeth they are, so mes would be a second helping of the same information and les does the job alone. Same shape every time: je me lave les mains, je me coupe les ongles, il se gratte la tête.

The pattern reaches past reflexive verbs: elle lui a pris la main (“she took his hand”), j’ai mal à la tête (“my head hurts”). Possessives come back when the body part is described or the owner is not obvious — ses longs cheveux bouclés, sa main tremblait. A morning routine is the fastest place to drill it: je me réveille, je me lève, je me lave le visage, je me brosse les dents, je m’habille.