25,000-Year-Old Teeth in Indonesia Reveal Earliest Known Habitual Drug Use

Archaeologists have discovered the oldest known evidence of habitual human drug use in fossilized teeth found in South Sulawesi, Indonesia. The findings suggest that prehistoric humans used psychoactive substances for pain relief and stimulation long before the dawn of agriculture.

Analysis of the teeth, which date back between 16,000 and 25,000 years, revealed deep, rounded grooves consistent with the habit of sucking on whole betel nuts. Biomolecular testing identified residues of arecoline, the principal psychoactive alkaloid found in the seed of the Areca catechu palm. This evidence predates any previously published records of habitual substance use by thousands of years.

A Prehistoric Tradition

Betel nut is currently the fourth most widely consumed psychoactive substance globally, trailing only alcohol, caffeine, and nicotine. While modern users typically prepare a "quid" by mixing the nut with slaked lime, the Sulawesi findings indicate an earlier, simpler method of consumption. Researchers believe these early humans simply sucked on the nuts to extract their numbing and stimulant effects, with pain relief likely serving as the primary goal of the practice.

Implications for Human History

This discovery shifts the timeline of human drug history deep into the Late Pleistocene. By predating previous records of habitual drug use—some of which were dated to roughly 3,500 years ago in Thailand—by at least 3,000 years, the study proves that substance use for medicinal or psychoactive purposes existed well before the Neolithic advent of farming approximately 12,500 years ago. It establishes a deep prehistoric link to a cultural tradition that remains widespread across the Asia-Pacific region today.

The Cost of Consumption

Beyond the cultural timeline, the discovery highlights an ancient struggle with addiction and health. The research suggests the practice may have created a "vicious cycle" for prehistoric foragers. Sucking the nuts provided temporary relief from pain, but the habit simultaneously damaged the teeth, creating new toothaches that drove the users to consume more of the substance for relief.

Future Research

As researchers continue to analyze Late Pleistocene sites in Southeast Asia, the focus remains on whether other psychoactive plants were utilized during this era. While the arecoline residues provide a concrete link to betel nut use, further study is needed to determine how widespread this habit was among other prehistoric populations in the region and how it influenced early human social structures.