The hidden limits of food system resilience under repeated climate shocks in sub-Saharan Africa

Abstract Food systems in sub-Saharan Africa are increasingly exposed to severe climate shocks, yet the point at which resilience fails remains unclear. We test a limits-to-resilience hypothesis using a balanced panel of 32 countries from 1990 to 2023, combining a Food System Resilience Index (FSRI) with five dimensions of shock exposure to identify the shock intensity at which FSRI no longer buffers undernourishment. We identify a resilience threshold at 30% population affected by droughts or floods (95% CI: 24–36%), below which FSRI reduces undernourishment, and above which protection disappears. Resilience erodes non-linearly, and repeated shocks impose a substantial hidden burden: observed undernourishment exceeds the no-shock counterfactual by 3.5 percentage points, equivalent to 18 million additional undernourished people per year. Eastern and Central Africa, including Somalia, Zambia and the Democratic Republic of the Congo, show the highest combined exposure, low resilience and severe food insecurity. The threshold is stable across time, geography and alternative nutritional outcomes, including child stunting. These findings identify a measurable limit to food system resilience and support proactive, tiered interventions before coping capacity is exhausted.