Driving Sustainable Food Choices: How to Craft an Effective Sustainability Labeling System

An important step in averting climate change is shifting consumers' diets to contain less meat. While preliminary work suggests sustainability labels can shift consumers' preferences, there is no clear guidance on what makes an effective labeling system. Across five experiments (N=6,001), we find that multi-icon systems (traffic light) are the most effective in reducing the carbon impact of consumers' choices, but also generated the most negative attitudes toward the restaurant. We further find that single-icon systems (e.g., labeling only sustainable options) are effective at shifting consumer choices, particularly when combined with numeric information (e.g., kg of CO2), and generally produce no negative attitudes relative to control. These results replicate using an incentive-compatible design and an externally valid population (tech employees). Overall, we provide a systematic empirical investigation of different approaches to sustainability labeling. We conclude by discussing limitations, future directions, and advice for implementing sustainability labels.