Achieving the Paris Agreement's 1.5°C target requires ambitious greenhouse gas (GHG) mitigation measures — such as expanding bioenergy crop production and large-scale afforestation — that compete directly with agricultural land. Prior multi-model assessments had consistently found that these policies, while reducing warming, drive up food prices and reduce calorie availability, putting an estimated 61 million additional people at risk of hunger by 2050 compared to a no-policy baseline. 

These studies however overlooked an important co-benefit of GHG mitigation: when fossil fuel use declines, co-emitted ozone precursors — methane (CH₄), nitrogen oxides (NOₓ), and volatile organic compounds (VOCs) — also fall, reducing surface-level ozone concentrations. Since elevated ozone is well established as a significant driver of crop yield losses (currently causing an estimated $34–45 billion in annual agricultural damage globally), this accompanying air quality improvement has direct positive consequences for food production that previous assessments had not captured. 

By systematically decomposing the individual contributions of climate change, mitigation policy, and ozone reduction to food security outcomes, the study found that ozone reduction accompanying stringent mitigation could lift approximately 8.4 million people out of hunger risk by 2050 — offsetting around 15% of the negative hunger impact caused by mitigation policies. The effect was geographically concentrated: India and Sub-Saharan Africa, the regions bearing the greatest current hunger burden, accounted for 56% of this global reduction, with India alone seeing a 39% offset of mitigation's negative impact, driven primarily by substantial gains in wheat production under lower ozone stress. 

The study's findings carry two important policy implications. First, future assessments of climate mitigation must explicitly account for ozone co-benefits, as omitting them leads to a systematic overestimation of mitigation's adverse effects on food security. Second, even after incorporating ozone reduction benefits, stringent climate mitigation still results in a net increase in global hunger risk relative to the no-policy baseline — meaning ozone improvements alone are insufficient to reconcile the tension between ambitious climate action and SDG2 (Zero Hunger).