24. Pee Was Used to Brush Teeth in the Roman World
The ancient Roman poet Catullus (circa 84 – circa 54 BC) once insulted a man named Egnatius, whose smile the poet seems to have disliked. It reveals something unusual about Romans’ day-to-day lives: they cleaned their mouths with pee. As the poet put it in his put down: “There’s nothing more foolish than foolishly smiling. Now you’re Spanish – in the country of Spain what each man [urines], he’s used to brushing his teeth and red gums with, every morning, so the fact that your teeth are so polished just shows you’re more full of [urine]“.
The abnormal practice decried was that Egnatius smiled too much, which was bad because smiles were presumably worthless. The diss was not about the cleaning-one’s-mouth-with-pee bit: for Romans, that was perfectly normal. Urine’s active ingredient is ammonia, which the body secretes in the form of urea. Today, we use ammonia in many things, from explosives to cleaning products to agricultural fertilizers. Not only will ammonia remove stubborn stains from your bathtub and oven, it will also leave your dishes and glasses glossy and shiny.