Climate change, hunger, and rural health through the lens of farming styles: an agent-based model to assess the potential role of peasant farming

Abstract Background Undernutrition is a major contributor to the global burden of disease, and global-level health impact models suggest that climate change-mediated reductions in food quantity and quality will negatively impact undernutrition. These models, however, capture just some of the processes that will shape future nutrition. We aimed to assess how different farm development trajectories might impact on hunger and health-supporting conditions in rural areas under climate change. Methods We developed an agent-based model in which producer-consumer smallholders practise different styles of farming in the global food system. The model represents a hypothetical rural community in which subsistence farmers can develop their farm by adopting an entrepreneurial style (highly market dependent) or by maintaining a peasant style (agroecology). The model was parameterised using globally representative average estimates (eg, the rate of climate change, crop yields, and weather-related losses) from the existing literature. We used the model to explore how patterns of farming styles, under various style preference, climate, policy, and price transmission scenarios, impact on hunger and health-supporting conditions (ie, incomes, work, inequality, and real land productivity) in rural areas. Findings Simulations without climate change or agricultural policy found that style preference patterns influence production, food price, and incomes, and that there were trade-offs between them. For instance, entrepreneurial-oriented futures had the highest production and lowest prices but were simultaneously those in which farming livelihoods tended to be inviable. Simulations with climate change and agricultural policy found that peasant-orientated agroecology futures had the highest production and prices equal to or lower than those under entrepreneurial-oriented futures, and better supported health in rural areas. There were, however, contradictory effects on nutrition, with benefits and harms for different groups. Interpretation Collectively, the findings suggest that when attempting to understand how climate change might affect future nutrition and health, patterns of farming styles—along with the fates of the households that practise them—are of importance. These issues, including the potential role of peasant farming, have been neglected in previous global-level climate-nutrition modelling, but go to the heart of current debates on the future of farming, and thus should be given more prominence in future work. Funding None.