Ancient Vietnam's blackened-teeth beauty trend traced to 2000 years ago

A new study analyzing three preserved teeth from northern Vietnam shows that ancient Vietnamese people deliberately blackened their teeth with an iron-rich paste for at least 2,000 years, using plant tannins and iron salts with a multi-day preparation process. The practice extended from the Iron Age to about 400 years ago, signaling beauty, adulthood, and social identity, and was not simply the result of betel chewing; the findings highlight long cultural continuity in the region.