Climate change may lead to the inability of millions of people to afford a healthy diet

The Food and Agriculture Organization (FAO) of the United Nations has called for the food system worldwide to shift from 'feeding people' to 'nourishing people', with the aim of improving the affordability of a diverse diet to better meet health needs. Achieving this goal requires reducing poverty and advancing agricultural development. However, climate change negatively impacts agricultural yields and food prices, diminishing these efforts. The extent to which climate change affects the affordability of healthy diets and their regional variations remains unclear. In this study, the impact of climate change on the affordability of healthy diets under different scenarios was assessed by coupling a climate-crop yield model with integrated assessment model GCAM7. We found that under the high-emission scenario (SSP5-unconstrained), the impacts of climate change, including global crop yield reductions and consequent increases in food prices, lead to an additional 70 million people globally will be unable to afford healthy diets by the end of the century, despite significant economic growth. Under the low-emission scenario SSP1-2.6, the impact on the food system is less than one-tenth that under SSP5-unconstrained. In all scenarios, developing regions are significantly more affected than wealthier regions, despite contributing less to climate change. In addressing climate change, we must acknowledge the varying vulnerabilities in affordability across different regions and populations. Effective mitigation measures are essential to ensure that everyone, regardless of their location, can access a healthy diet.