Traffic light labelling of meals to promote sustainable consumption and healthy eating.

The focus of the present study is to examine the impact of behavioral interventions designed to encourage consumer change around food choices in line with more sustainable consumption as well as healthy eating. More specifically, as a potential method of persuasion, we test the effect of the provision of information using traffic light labelling attached to different meal options signalling their impact on the environment (e.g. carbon emission levels) as well as on their health (e.g., calorific content). While traffic light labelling has shown some success in encouraging both healthy and sustainable food consumption, there is still limited work demonstrating the impact on choice behavior. The present study includes two experiments (Experiment 1, N = 120 [approximately 40 per condition], Experiment 2, N = 297 [approximately 95 per condition]). They examined the impact of the presentation of single (traffic light labelling of calorific content, traffic light labelling of carbon emission levels) and dual (both calorific content and carbon emission levels) traffic light labels in a hypothetical simulated canteen environment. For some participants, the traffic light labels were supplemented with additional information which either contained general information regarding calorific content and carbon emissions, or specific reference values regarding the relationship between particular calorific or carbon emission levels to other activities (i.e. walking, driving). The Results from both experiments show that, compared to baseline, the presence of traffic light labels led to positive shifts towards lower carbon emission and lower calorific content meals. Both general and specific information supported positive behavioral change towards healthier and sustainable meal choices. The findings are discussed in relation to existing work examining the impact of behavioral interventions designed to support positive change in consumer behavior.