Diet and Oral Health in Pre-Columbian South America: A Comparative Study of Hunter-Gatherers and Horticulturalists From the Lower Paraná Wetland (Argentina)

The relationship between diet and oral health has long been explored in archaeology, with significant differences observed between populations with distinct subsistence strategies. This study examines the prevalence of dental caries, antemortem tooth loss (AMTL), periapical lesions, dental calculus, and occlusal wear in hunter-gatherer and horticulturalist populations from the Lower Paraná wetland (southern La Plata Basin, Argentina). Our primary objective is to evaluate how dietary differences influenced oral health in these pre-Columbian groups and contextualize the findings within broader pre-Columbian trends from Argentina. The analyzed sample includes skeletal and dental remains from 178 hunter-gatherers (26 sites) and 29 horticulturalists (3 sites), dated between < 2000–500 and 700–300 ¹⁴C years bp, respectively. Statistical comparisons employed chi-square tests, Monte Carlo permutations, odds ratios, bootstrap tests, and generalized linear models. Wear rates were calculated using principal axis methods. Results indicate a significantly lower prevalence of dental caries in hunter-gatherers (2%) compared to horticulturalists (8.8%), linked to lower carbohydrate intake. AMTL and occlusal wear were more frequent in hunter-gatherers (AMTL = 4% vs. 0.8%), likely influenced by dietary abrasives and protein-rich consumption. No statistical differences were found between populations in periapical lesions and dental calculus, suggesting multifactorial origins beyond diet alone. In contrast to expectations, male hunter-gatherers exhibited higher caries (2% vs. 0.5%) and wear rates than females, potentially related to dietary habits or paramasticatory activities. These findings align with global trends, situating hunter-gatherers among low-caries/high-wear populations and horticulturalists within mixed-diet groups. This study contributes to understanding dietary impacts on oral health in pre-Columbian South America, emphasizing the need for expanded samples to refine sex-based and wear-related interpretations.