Agricultural Diversification, Nutrition and Health Outcomes in Nigeria

This study examines long-run and short-run relationships between agricultural diversification, nutrition and health outcomes in Nigeria using annual time-series data covering 1990–2024. Agricultural diversification is represented by a composite index incorporating crop, land-use and agricultural value-added diversity, while nutrition and health outcomes are measured using composite deprivation indices. The study employs the Augmented Dickey-Fuller (ADF) unit root test, Autoregressive Distributed Lag (ARDL) bounds testing and error-correction modelling. The ARDL bounds tests indicate long-run relationships in nutrition and health models, with F-statistics of 4.933 and 14.327, respectively, exceeding their reported 5% upper critical bounds. The long-run estimates reveal a positive but statistically insignificant association between agricultural diversification and nutrition deprivation (β = 0.116, p = 0.896). Conversely, agricultural diversification exhibits a negative and statistically significant association with health deprivation (β = −1.287, p < 0.001). The short-run relationship with health deprivation is also negative and statistically significant (β = −2.974, p < 0.001). The error-correction coefficients of −0.662 and −1.156 for the nutrition and health models, respectively, indicate adjustment towards long-run equilibrium, with evidence of overshooting in the health model. However, residual serial correlation, borderline functional-form diagnostics and unresolved integration-order concerns necessitate cautious interpretation. The findings provide stronger statistical evidence of an association between agricultural diversification and health deprivation than between diversification and nutrition deprivation within the estimated models. The study recommends integrating agricultural diversification initiatives with policies that improve dietary quality, food accessibility, sanitation, healthcare delivery and household purchasing power to support sustainable improvements in nutritional and population-health outcomes.