Environmental impacts, nutritional profiles, and retail prices of commonly sold retail food items in 181 countries: an observational study

2024-01-24

AI Summary

This study investigates the associations among retail prices, environmental footprints (carbon and water), and nutritional quality across 811 food items in 181 countries. We integrate a global retail price database, life cycle assessment (LCA)-based environmental footprint estimates, and standardized nutrient profiling scores, employing hierarchical regression and within-category comparative analysis to conduct the first multinational, cross-food-group, multidimensional (price–environment–nutrition) empirical gradient analysis. Results challenge the prevailing assumption that sustainable diets are inherently more expensive: lower-priced foods—particularly animal-based products—exhibit significantly reduced carbon and water footprints (e.g., a 10% price decrease correlates with ~20 g CO₂e and ~5 L water reduction per 100 kcal). In contrast, the price–nutrition relationship is non-monotonic and highly category-dependent. These findings provide robust, policy-relevant evidence for designing effective interventions to advance sustainable dietary transitions.

Technology Category

• Search and Optimization: Evaluation and Analysis
• Machine Learning: Other Foundations of Machine Learning
• Game Theory and Economic Paradigms: Applications

Application Category

• Economics, Online Markets and Human Computation: Sustainability of Web economics
• Responsible Web: Sustainability and climate impact of web technologies
• Security and Privacy: Data transparency and provenance

Abstract

Affordability is often seen as a barrier to consuming sustainable diets. This study provides the first worldwide test of how retail food prices relate to empirically estimated environmental impacts and nutritional profile scores between and within food groups. We use prices for 811 retail food items commonly sold in 181 countries during 2011 and 2017, matched to estimated carbon and water footprints and nutritional profiles, to test whether healthier and more environmentally sustainable foods are more expensive between and within food groups. We find that within almost all groups, less expensive items have significantly lower carbon and water footprints. Associations are strongest for animal source foods, where each 10% lower price is associated with 20 grams lower CO2-equivalent carbon and 5 liters lower water footprint per 100kcal. Gradients between price and nutritional profile vary by food group, price range, and nutritional attribute. In contrast, lower-priced items have lower nutritional value in only some groups over some price ranges, and that relationship is sometimes reversed. These findings reveal opportunities to reduce financial and environmental costs of diets, contributing to transitions towards healthier, more environmentally sustainable food systems.

Problem

• Examine retail food prices versus environmental footprints globally
• Assess if healthier, sustainable foods are more expensive
• Compare price impacts on carbon and water footprints

Innovation

• Analyzed 48,316 retail food prices globally
• Matched prices to environmental and nutritional data
• Found cheaper items have smaller environmental footprints