Towards sustainable diets and farming systems through land use optimisation

Abstract The industrialised food system poses health and environmental challenges, raising concerns about its sustainability. Addressing these requires region-specific solutions that consider local agronomic and socio-economic conditions. This study examines how transforming the food system impacts land use and self-sufficiency in a defined region of a country. Using Wallonia as a case study, we modelled crop allocation across different pedoclimatic conditions and evaluated three diets—CURRENT, TYFA, and EAT-Lancet—under conventional and organic farming, with 30% or 10% food waste. Our results demonstrate that, regardless of farming practice, Wallonia cannot achieve self-sufficiency under the CURRENT diet. However, adopting the TYFA or EAT-Lancet diets would enable self-sufficiency and spare land for alternative uses, under conventional farming. Food waste reduction was pivotal for enhancing self-sufficiency under organic farming. This research offers a solid foundation for informing agri-food policies in Wallonia and can be extended to other regions seeking to improve local food security.