The new research team, led by Piyawit Moonkham at Chiang Mai University, analyzed hardened dental plaque from Bronze Age skeletons at the site of Nong Ratchawat. In one young woman\u2019s molars, they detected key compounds from betel nut that are known to boost alertness and euphoria. <\/p>\n\n\n\n
Other archaeologists welcome the technical breakthrough but say more evidence is needed before we can be sure this was already a widespread habit four thousand years ago.<\/p>\n\n\n\n
Betel nut, from daily pick me up to health concern<\/h2>\n\n\n\n
Betel nut is the seed of the areca palm, often wrapped in a betel leaf with slaked lime to form a chew called a quid. People across South and Southeast Asia have used it for thousands of years to stay awake, feel more talkative, or take the edge off a long day.<\/p>\n\n\n\n
Read More: A judge orders solar panels removed from a balcony, sparking an unexpected debate over saving electricity, neighbors, and the limits of home energy<\/a><\/h3>\n<\/div>\n<\/div><\/div>\n<\/div>\n\n\n\nToday it is still chewed by millions, and public health experts say it is now the fourth most commonly used psychoactive substance worldwide, after tobacco, alcohol, and caffeine. Long-term use is strongly linked to oral cancers, so health agencies and governments in places such as Thailand and India have pushed campaigns to discourage the habit and cut those risks.<\/p>\n\n\n\n
Moonkham, who grew up watching his grandparents chew betel nut, has suggested that people may also have turned to it for stress relief or even to cope with mental illness. That more nuanced view sits alongside modern warnings and helps explain why this small seed has held on in so many communities despite serious health concerns.<\/p>\n\n\n\n
Plaque time capsules at Nong Ratchawat<\/h2>\n\n\n\n
Since 2003, excavations at Nong Ratchawat in central Thailand have uncovered more than 150burials<\/a> from the Bronze Age. For the new research, scientists collected 36 tiny samples of dental calculus, the rock hard plaque that builds up on teeth before a deep cleaning at the dentist, from six individuals.<\/p>\n\n\n\nBecause calculus mineralizes in place and can trap food particles and chemical traces, it acts like a microscopic time capsule<\/a> of a person\u2019s diet and habits. The team then used sensitive chemical analysis to look for plant compounds that might still be preserved inside these gritty flakes.<\/p>\n\n\n\n![\"Ancient](\"https:\/\/www.ecoticias.com\/en\/wp-content\/uploads\/2026\/04\/4000-year-old-teeth-betel-remains-thailand-jaw.jpg\" "\\"\\"")
A close-up of an ancient jaw and teeth reflects the archaeological evidence that helped researchers identify traces of betel use in Bronze Age Thailand.<\/figcaption><\/figure>\n\n\n\nTo check that their method worked, the researchers mixed dried betel nut, pink limestone paste, betel leaves, tree bark, tobacco, and human saliva to make modern quids in the lab, then tested the red liquid that resulted. Those experimental samples gave them a clear chemical fingerprint that they could compare directly with the ancient plaque.<\/p>\n\n\n\n
The Bronze Age woman behind the evidence<\/h2>\n\n\n\n
In three calculus samples taken from different molars of a single woman, labeled Burial 11, the team detected the compounds arecoline and arecaidine. These chemicals are key ingredients in betel nut and also appear in other stimulant plants such as coffee and tobacco, where they have strong effects on the human body.<\/p>\n\n\n\n
Finding this chemical fingerprint in plaque suggests repeated chewing over time rather than a one time experiment, because residues slowly build up as a person keeps using the plant. <\/p>\n\n\n\n
\n\n\nRead More: A tectonic plate that had been \u201cdead\u201d for 200 million years has just reappeared beneath western North America, and scientists say it could be increasing seismic risk without anyone noticing<\/a><\/h3>\n<\/div>\n<\/div><\/div>\n<\/div>\n\n\n\nYet this woman\u2019s teeth showed no obvious red or black staining and her grave did not contain the usual shell fragments or tools linked to betel chewing, so the team suspects different preparation methods, careful cleaning, or later damage may have erased those visible clues.<\/p>\n\n\n\n
Senior author Shannon Tushingham of the California Academy of Sciences said their approach lets them “make the invisible visible,” turning hardened plaque into a record of everyday behavior rather than just something a hygienist scrapes away. <\/p>\n\n\n\n
The woman\u2019s grave goods, including stone beads, suggest she lived an ordinary life in her community, which makes her chemical traces all the more valuable for understanding routine practices rather than rare rituals.<\/p>\n\n\n\n
Debate over the earliest betel chewers<\/h2>\n\n\n\n
Not everyone is ready to call this the final word on when betel chewing began in Southeast Asia. Miriam Stark of University of Hawaii at Manoa notes that Nong Ratchawat has fewer radiocarbon dates and less detailed documentation than some other sites, and that only one of the six people sampled showed betel-related compounds.<\/p>\n\n\n\n
Other digs, including the nine thousand year old Spirit Cave in northwestern Thailand, have produced plant remains or stained teeth that many researchers link to betel use. For Stark, the new work is an important starting point that shows how dental calculus can answer old questions, but she argues it still needs to be combined with physical clues such as plant fragments and tools.<\/p>\n\n\n\n
\n\n\nRead More: December 1938, a call from a ship and an \u201cimpossible fish\u201d in South Africa: that’s how the day began when Marjorie Courtenay-Latimer turned 66 million years of science on its head<\/a><\/h3>\n<\/div>\n<\/div><\/div>\n<\/div>\n\n\n\nArchaeobotanist Cristina Castillo of University College London has also warned that compounds like arecoline may appear in several species within the Areca palm family, not just the classic betel nut. In a 2022 study in the journal Economic Botany<\/em>, she argued that new chemical methods should, for the most part, be backed up by traditional archaeological evidence before scientists rewrite cultural histories. <\/p>\n\n\n\nResearchers writing in follow-up pieces have echoed that caution while highlighting how new techniques are reshaping the study of ancient plant use.<\/p>\n\n\n\n
The main study has been published in the journal Frontiers in Environmental Archaeology<\/em><\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":"Four thousand years ago, at a small cemetery in what is now central Thailand, one woman may have been getting … <\/p>\n
Because calculus mineralizes in place and can trap food particles and chemical traces, it acts like a microscopic time capsule<\/a> of a person\u2019s diet and habits. The team then used sensitive chemical analysis to look for plant compounds that might still be preserved inside these gritty flakes.<\/p>\n\n\n\n To check that their method worked, the researchers mixed dried betel nut, pink limestone paste, betel leaves, tree bark, tobacco, and human saliva to make modern quids in the lab, then tested the red liquid that resulted. Those experimental samples gave them a clear chemical fingerprint that they could compare directly with the ancient plaque.<\/p>\n\n\n\n In three calculus samples taken from different molars of a single woman, labeled Burial 11, the team detected the compounds arecoline and arecaidine. These chemicals are key ingredients in betel nut and also appear in other stimulant plants such as coffee and tobacco, where they have strong effects on the human body.<\/p>\n\n\n\n Finding this chemical fingerprint in plaque suggests repeated chewing over time rather than a one time experiment, because residues slowly build up as a person keeps using the plant. <\/p>\n\n\n\n Yet this woman\u2019s teeth showed no obvious red or black staining and her grave did not contain the usual shell fragments or tools linked to betel chewing, so the team suspects different preparation methods, careful cleaning, or later damage may have erased those visible clues.<\/p>\n\n\n\n Senior author Shannon Tushingham of the California Academy of Sciences said their approach lets them “make the invisible visible,” turning hardened plaque into a record of everyday behavior rather than just something a hygienist scrapes away. <\/p>\n\n\n\n The woman\u2019s grave goods, including stone beads, suggest she lived an ordinary life in her community, which makes her chemical traces all the more valuable for understanding routine practices rather than rare rituals.<\/p>\n\n\n\n Not everyone is ready to call this the final word on when betel chewing began in Southeast Asia. Miriam Stark of University of Hawaii at Manoa notes that Nong Ratchawat has fewer radiocarbon dates and less detailed documentation than some other sites, and that only one of the six people sampled showed betel-related compounds.<\/p>\n\n\n\n Other digs, including the nine thousand year old Spirit Cave in northwestern Thailand, have produced plant remains or stained teeth that many researchers link to betel use. For Stark, the new work is an important starting point that shows how dental calculus can answer old questions, but she argues it still needs to be combined with physical clues such as plant fragments and tools.<\/p>\n\n\n\n Archaeobotanist Cristina Castillo of University College London has also warned that compounds like arecoline may appear in several species within the Areca palm family, not just the classic betel nut. In a 2022 study in the journal Economic Botany<\/em>, she argued that new chemical methods should, for the most part, be backed up by traditional archaeological evidence before scientists rewrite cultural histories. <\/p>\n\n\n\n Researchers writing in follow-up pieces have echoed that caution while highlighting how new techniques are reshaping the study of ancient plant use.<\/p>\n\n\n\n The main study has been published in the journal Frontiers in Environmental Archaeology<\/em><\/a>.<\/p>\n","protected":false},"excerpt":{"rendered":" Four thousand years ago, at a small cemetery in what is now central Thailand, one woman may have been getting … <\/p>\nThe Bronze Age woman behind the evidence<\/h2>\n\n\n\n
Read More: A tectonic plate that had been \u201cdead\u201d for 200 million years has just reappeared beneath western North America, and scientists say it could be increasing seismic risk without anyone noticing<\/a><\/h3>\n<\/div>\n<\/div><\/div>\n<\/div>\n\n\n\n
Debate over the earliest betel chewers<\/h2>\n\n\n\n
Read More: December 1938, a call from a ship and an \u201cimpossible fish\u201d in South Africa: that’s how the day began when Marjorie Courtenay-Latimer turned 66 million years of science on its head<\/a><\/h3>\n<\/div>\n<\/div><\/div>\n<\/div>\n\n\n\n