The rise of on-demand grocery delivery and unequal access to fresh food in a high-density city: Evidence from Shenzhen, China.

Access to fresh food is essential for healthy diets and for reducing place-based health inequalities. In Chinese cities, on-demand grocery platforms and click-and-collect services are creating hybrid food environments that combine physical retailers with digital access, yet their equity implications remain unclear. This study develops a population-adjusted Fresh Food Environment Index (FFEI) integrating service coverage from traditional fresh food retailers, online pickup nodes, and fine-grained population distribution data. Using 665 neighborhoods in Shenzhen, China, we examine how online access reshapes spatial and social inequalities in fresh food environments. Results show that online access brings limited overall improvement but uneven redistributive effects. After online access was incorporated, only 13.08% of neighborhoods changed classification, with deterioration slightly exceeding improvement. Rather than compensating for traditional access deficits, online provision reinforced a core-periphery pattern: central districts remained relatively disadvantaged despite higher aggregate supply because dense demand reduced per capita service capacity. Social exposure also varied by age, household structure, income, employment status, and digital capability. Older residents and some family groups were more exposed to unfavorable transitions, whereas some lower-income groups appeared to benefit from online access. These findings suggest that digital grocery platforms redistribute, rather than resolve, fresh food access inequalities. Equity-oriented food governance should target neighborhoods facing combined physical and digital service failures and complement platform expansion with offline provision, digital inclusion, and population-sensitive planning.