Environmental impacts and monetary costs of healthy diets worldwide

TL;DR

This study quantifies the environmental and monetary impacts of healthy diets worldwide, showing that low-emission diets are feasible and cost-effective, primarily influenced by animal-source foods and staples.

Contribution

It provides a global analysis of how diet choices affect emissions and costs, highlighting policy pathways for sustainable and healthy eating.

Findings

Low-emission healthy diets emit 0.67 kg CO2e.

Least expensive diets emit 1.65 kg CO2e and cost $9.96.

Animal foods and staples drive most emission differences.

Abstract

Using real-world food price and greenhouse gas (GHG) emissions data for locally available food items in 171 countries, we measure how healthy diets could be obtained with the lowest possible emissions, compared to costs and emissions of the least expensive options and foods most commonly consumed. We find that foods with the lowest GHG emissions for a healthy diet would emit 0.67 kg CO2e. A healthy diet using the least expensive items in each country would emit 1.65 kg CO2e and cost 9.96. Ninety-one percent of the difference in emissions between the lowest-cost and lowest-emissions diets is driven by animal-source foods and starchy staples. Other food groups, especially fruits and vegetables, vary widely in cost but not in emissions. Results show how changes in food policy and choice can most cost-effectively support healthier and more sustainable diets worldwide.