The consumption of areca nuts, one of the most widely used psychoactive substances in the world, may have begun up to 25,000 years ago among some communities in Indonesia. The conclusion results from an archaeological and biochemical study conducted by researchers from Griffith University and Indonesian institutions, who identified traces of this practice in human remains found on the island of Sulawesi.
The team, led by Adam Brumm, from the Australian Research Centre for Human Evolution, analyzed skeletal remains of two hunter-gatherers. One individual lived between 25,000 and 16,000 years ago and the other between 7,600 and 6,300 years ago. Both exhibited an unusual pattern of dental wear, with deep, rounded grooves, which the researchers linked to the habit of sucking on whole areca nuts.
The biochemical analysis of the dental tissues also detected arecoline, the primary psychoactive alkaloid present in the areca nut, reinforcing the hypothesis of habitual consumption.
The discovery substantially pushes back the known chronology of the consumption of this substance. Until now, theories about the earliest traditions of psychoactive substance use pointed mainly to the period after the appearance of agriculture, including the consumption of fermented alcoholic beverages around 13,000 years ago in the current territory of Israel.
The areca nut is obtained from the palm Areca catechu and is currently consumed by hundreds of millions of people from India to the South Pacific. It is often mixed with slaked lime and other ingredients, forming a preparation known as “quid,” which is sucked to produce effects such as mild euphoria and increased alertness. It is considered the fourth most widely consumed psychoactive substance in the world, after alcohol, caffeine and nicotine.
A previously unknown form of consumption
The researchers conducted experiments with areca nuts submerged in artificial saliva and analyzed the compounds released through cloned human receptors. The results showed that sucking on the whole nut is sufficient to release amounts of arecoline capable of producing physiological effects and altering brain activity.
According to the team, this practice would be different from the way the areca nut is habitually consumed today. The lime used in the preparation of the “quid” triggers a chemical reaction that increases the availability of arecoline to the body, accelerating its absorption.
The rarity of preserved areca seeds in archaeological contexts had until now hindered the identification of the origins of this practice. The specific pattern of dental wear identified in the Sulawesi remains, therefore, constitutes a new bioarchaeological marker of the habitual consumption of the plant.
A habit that could ease pain but damage the teeth
The researchers acknowledge that the psychoactive effect of sucking on whole nuts would probably be milder than that produced by the “quid” currently used. However, the practice would have had significant consequences for oral health.
The individuals analyzed exhibited severe dental problems. Arecoline has natural analgesic properties, so the team considers that the consumption of the areca nut could have been used, among other reasons, to relieve toothache.
The problem is that the hard and abrasive seeds caused progressive wear on the teeth. In some cases, this wear would have been sufficient to expose the dental pulp chamber, causing intense pain, difficulties in eating, and a higher risk of chronic dental infections.
The researchers thus acknowledge the possibility that a cycle may have formed in which plant consumption initially helped relieve pain, but with prolonged use it worsened oral health and could contribute to maintaining the habit itself.
A practice preceding agriculture
Published in the journal Science Advances, the study suggests that habitual consumption of a psychoactive substance was already part of the practices of some hunter-gatherer communities tens of thousands of years before the appearance of agriculture.
The researchers consider that the evidence found in Sulawesi, dating back as far as 25,000 years, could constitute the oldest known evidence of habitual use of a plant-based drug, showing that some practices associated with the consumption of psychoactive substances have roots much older than previously thought.
