Did the Ancient Romans Really Wash Their Teeth with Urine?

One of the most commonly repeated factoids about the ancient Romans is that they supposedly brushed their teeth with urine, because urine can be used to make teeth appear whiter. This factoid is usually presented to elicit feelings of shock and disgust. For instance, here is the introduction to an article by Nicholas Sokic titled “WFT: Romans used pee to whiten teeth,” published on the website Healthing on 29 January 2020:

“The Romans contributed greatly to civilization — roads, cement, aqueducts, the postal service — but not all of their creations lived to the present day, and some deservedly so. Ancient Romans used to use both human and animal urine as mouthwash in order to whiten their teeth.”

It is true that several ancient Roman and Greek sources do mention the use of urine to whiten teeth. None of these sources, however, portray this as a Roman practice. Instead, they unanimously and consistently portray it as a disgusting and barbarous practice associated with the Celtiberians, a group of Celtic peoples who lived in the central and eastern parts of the Iberian Peninsula. Furthermore, because there are no surviving Celtiberian records that confirm the alleged practice of using urine to whiten teeth, it is unclear how common this practice really was, or even whether it was something that the Celtiberians really did at all.

Catullus on Egnatius

One of the earliest references to the use of urine to whiten teeth comes from the Roman poet Gaius Valerius Catullus (lived c. 84 – c. 54 BCE). By the time Catullus was writing, the Celtiberians were mostly living under Roman rule, but Italian Romans (such as Catullus himself) still regarded them as foreign and barbarous.

Catullus introduces a character in his “Carmen 37” named Egnatius, whom he describes as a Celtiberian. Catullus mocks Egnatius for following Celtiberian customs, which he portrays as barbaric and disgusting. Chief among these is the use of urine for whitening teeth. Catullus writes, in lines 17–20:

“tu praeter omnes une de capillatis,
cuniculosae Celtiberiae fili,
Egnati, opaca quem bonum facit barba
et dens Hibera defricatus urina.”

This means, in my own translation:

“You before all—one from the long-haired people,
son of rabbit-infested Celtiberia,
Egnatius, whom a shady beard makes good
and teeth scrubbed down with Hibernian urine.”

Catullus devotes the entirety of “Carmen 39” to ruthlessly mocking Egnatius for his smile and his alleged use of urine as a tooth-whitener. He writes, in lines 17–21:

“nunc Celtiber es: Celtiberia in terra,
quod quisque minxit, hoc sibi solet mane
dentem atque russam defricare gingivam,
ut quo iste vester expolitior dens est,
hoc te amplius bibisse praedicet loti.”

This means, in my own translation:

“Now you [i.e., Egnatius] are a Celtiberian; in the Celtiberian land,
everyone pisses and they are accustomed in the morning
to scrub down their teeth and red gums
so that, when your tooth is shinier,
this only proves that you have drunk more urine.”

There are, of course, many problems with using Catullus as a source in this context. Notably, he was a poet and his purpose was to write satire, not to accurately document authentic Celtiberian customs. Furthermore, there is no evidence that Catullus ever personally visited Celtiberia, so his information about Celtiberian practices can only be second-hand. Nonetheless, as we shall see, the claim that the Celtiberians washed their teeth with urine is also attested in Greek ethnographic sources.

ABOVE: Photograph from Wikimedia Commons of an imaginative modern bust of the Roman poet Catullus, showing what the artist imagined Catullus might have looked like. (No one knows what he actually looked like.)

Diodoros Sikeliotes

Another early source that mentions the Celtiberians using urine to whiten their teeth is the Greek historian Diodoros Sikeliotes (lived c. 90 – c. 30 BCE), a longer-lived contemporary of Catullus. Diodoros describes the Celtiberians as a generally very clean and respectable people, but, in his Library of History 5.33.5, he insists that they have one very bizarre and disgusting custom. He writes, as translated by C. H. Oldfather:

“And a peculiar and strange custom obtains among them: Careful and cleanly as they are in their ways of living, they nevertheless observe one practice which is low and partakes of great uncleanness; for they consistently use urine to bathe the body and wash their teeth with it, thinking that in this practice is constituted the care and healing of the body.”

Notice that Diodoros states that the Celtiberians not only washed their teeth with urine, but also literally bathed in it. This is a new claim that is not found in Catullus.

ABOVE: Nineteenth-century fresco depicting how the artist imagined Diodoros Sikeliotes might have looked. (No one knows what he actually looked like.)

Strabon of Amaseia

Another slightly later source that mentions the Celtiberians washing their teeth and bodies with urine is the Greek geographer Strabon of Amaseia (lived c. 64 BCE – c. 24 CE). Strabon writes the following words in his Geographika 3.4.16, as translated by H. C. Hamilton and W. Falconer:

“They do not attend to ease or luxury, unless any one considers it can add to the happiness of their lives to wash themselves and their wives in stale urine kept in tanks, and to rinse their teeth with it, which they say is the custom both with the Cantabrians and their neighbours. This practice, as well as that of sleeping on the ground, is common both among the Iberians and Kelts.”

Put together, the testimonies of Catullus, Diodoros, and Strabon clearly demonstrate that some people in the Roman world believed that the Celtiberians used urine to wash and whiten their teeth.

ABOVE: Illustration from 1584 by the French engraver André Thevet, depicting how he imagined the geographer Strabon of Amaseia might have looked (No one knows what he actually looked like.)

Did the Celtiberians actually do this?

Unfortunately, while it is clear that many Greeks and Romans believed that whitening teeth using urine was a widespread practice among the Celtiberians, it is not clear how common this practice really was—or, indeed, whether the Celtiberians really engaged in it at all. It’s important to remember that we have no independent confirmation of the practice of brushing teeth and bathing with urine from any actual Celtiberian source.

Furthermore, although we don’t have any evidence to suggest that Roman people in Italy ever regularly washed their teeth with urine, they were certainly aware that stale urine can act as a bleaching agent, since Roman fullers did use stale urine to bleach clothes. It is therefore quite possible that some Greek or Roman author may have simply made up the whole story about Celtiberians washing their teeth and bodies with stale urine in order to portray them as disgusting and barbarous by taking something that the Romans themselves normally only did with clothes and applying it to the body itself.

Unfortunately, until further evidence surfaces, we probably cannot draw any definitive conclusions on this matter.