Redistributed, Not Reduced: The Role of International Trade in Global Food Supply Sustainability

Abstract: Global food systems must balance productivity with environmental sustainability amid climate change, geopolitical shocks, and unevenly distributed natural resources. This study introduces the Food Supply Sustainability Index (FSSI), a transparent, composite measure of the sustainability of a nation’s food production including international trade, and future climate-driven trade dynamics, with a distance-to-target method. 

Using FAO and IFPRI data, the FSSI categorises countries into five sustainability classes across three pillars: carbon footprint, soil degradation, and water stress. The results show high-income countries produce food less sustainably, while low-income countries do so more sustainably yet are more vulnerable to climate change and trade disruptions. The FSSI therefore recognises that trade redistributes rather than removes environmental risk, creating a more evenly distributed yet persistent global vulnerability to shocks. Under future climate scenarios, the index identifies that sustainability worsens in poorer regions, especially Sub-Saharan Africa, exposing countries to food insecurity. 

By combining multiple environmental dimensions into a single metric, the FSSI enables countries to benchmark sustainability performance and identify priority areas for intervention. The FSSI supports policies such as aligning imports with sustainability criteria, diversifying suppliers toward lower-impact origins, and supporting sustainable intensification in low-income settings. The FSSI provides a replicable, policy-relevant tool to assess, compare, and communicate global food system sustainability.