A Systems Analysis of the Drivers and Consequences of Nutrition Transition in Urban Nigeria: Theoretical Frameworks and Empirical Evidence From Lagos and Kano

Nutrition transition in Nigeria is proceeding at a pace that outstrips the policy and institutional responses designed to address its health consequences. This study develops and tests a systems-level analytical framework to explain the drivers and health consequences of nutrition transition in two contrasting urban centres: Lagos, representing South West Nigeria, and Kano, representing the North West. Using a convergent mixed-methods design, the study synthesised data from a longitudinal dietary survey of 800 adults over 18 months, a food environment assessment mapping 600 food outlets in both cities, and 30 key informant interviews with policymakers and food industry actors. The analytical framework draws on the political economy of food systems, behavioural economics, and ecological nutrition theories. Quantitative panel data were analysed using fixed-effects regression, while qualitative data were subjected to framework analysis. Results demonstrated that urbanisation speed, food industry marketing activity, trade liberalisation effects on food prices, and weakening of traditional food norms were the dominant systems-level drivers. Dietary pattern shifts toward processed foods were more advanced in Lagos but accelerating in Kano. Diet-related chronic disease indicators including obesity and hyperglycaemia were significantly associated with exposure to ultra-processed food environments. The study contributes an original dual-city analytical framework and policy propositions for food system governance reform in Nigerian urban contexts. Keywords: nutrition transition, food systems, urban Nigeria, Lagos, Kano