Vitamin D deficiency and the ancient city: Skeletal evidence across the life course from the Roman period site of Isola Sacra, Italy

Taking the innovative step of considering individuals of all age groups and disease states via aspects of a life course perspective, this study aims to shed light on biocultural factors contributing to vitamin D deficiency in the Roman period assemblage from Isola Sacra, Italy (1st–3rd century AD) comprising 678 individuals (307 nonadults, 371 adults). Active and healed deficiency were identified in nonadults (<20 years) and adults (20 years and older) using standard paleopathological criteria based on macroscopic, radiographic, and histological evidence. The overall prevalence of skeletal evidence for vitamin D deficiency was 7.5% in nonadults (23/307 individuals) and 5.7% in adults (21/371 individuals); the age distribution of lesions indicates the importance of deficiency in infancy and adolescence, but not in older adulthood. Biocultural factors, including dense occupation, multi-storey buildings, and Roman childcare practices, probably influenced the development of vitamin D deficiency. Patterning of lesions suggests important biological and social links between infants and young children and their adult caretakers, highlights adolescence as a period of social transition and rapid growth that may affect susceptibility to deficiency, and reveals resilience in older adulthood that may relate to differential resource access in this group.