The biocultural effects of European contact varied considerably throughout the Americas. Some populations were decimated by colonialism, while others benefited from trade relationships and access to new technologies. It has been suggested that initial contact with European fur traders and explorers was economically favourable for Plains village populations, thereby facilitating a period of cultural florescence. In this study, we evaluate the hypothesis that Plains groups were better off than their predecessors during the initial contact period by comparing frequencies of enamel hypoplasia, cribra orbitalia, and porotic hyperostosis in pre‐ and post‐contact Arikara skeletal assemblages. We included both juveniles and adults in our sample to capture variation in the stress experience of different segments of the population. Our analysis revealed similarly low frequencies of cribra orbitalia in the pre‐ and post‐contact groups and no observed cases of porotic hyperostosis. Enamel hypoplasia, however, was significantly more prevalent among post‐contact Arikara villagers when compared to their pre‐contact counterparts, which suggests that stress levels were higher after European contact. Additionally, enamel hypoplasia was most common among post‐contact juveniles. The elevated frequency of enamel hypoplasia in the post‐contact sample combined with the low frequencies of cribra orbitalia and porotic hyperostosis suggests that disease stress, rather than nutritional deficiencies, was likely responsible for the decline in overall health following European contact. These results also suggest that juveniles are sensitive indicators of systemic stress within a population and should be included in bioarchaeological analyses of prehistoric health when available. Copyright © 2015 John Wiley & Sons, Ltd.