Human dietary shifts reflect the impact of social turmoil during the 3rd to 6th centuries in the Guanzhong Region, China

The Wei, Jin, and Southern and Northern Dynasties (220–589 CE) in China were marked by frequent warfare, political fragmentation, and extensive ethnic integration, resulting in profound social and economic instability. To explore how such turmoil affected subsistence strategies in the Guanzhong region, we conducted stable isotope analysis of 58 human remains from the Dengjiapo cemetery in Xi'an, spanning the Wei-Jin, Sixteen Kingdoms, and Northern Wei periods. The results reveal a mixed C₃/C₄-based diet that remained relatively stable across centuries. However, δ¹⁵N values declined significantly during the Later Qin of the Sixteen Kingdoms and Northern Wei. This suggests reduced and unstable access to animal protein, probably reflecting the detrimental effects of warfare and social unrest on animal husbandry and living standards. In a broader temporal perspective, comparisons with isotopic data from the Eastern Zhou to the Sui periods indicate a gradual dietary transition from C₄ dominance to a mixed C₃/C₄ pattern. This shift likely reflects adaptive agricultural strategies under sustained instability, with increased reliance on C₃ foods to mitigate food shortages. These findings provide valuable isotopic evidence of dietary adaptations to social turmoil and environmental stress, offering new insights into how ancient communities in the Guanzhong region coped with economic and social challenges.