Nutritional and economic impact of 5 alternative front-of-pack nutritional labels: experimental evidence

We study, in a laboratory framed field experiment, the impact of five Front of Pack labels (FOPL) on the nutritional quality and cost of a daily consumption basket. We employ a difference in difference experimental design, between subjects, to cleanly identify the impact of FOPL. 691 subjects issued from the general population shop twice within a catalog of 290 products: a first time without and a second unannounced time with labels. Purchases are real. We test five different labels and compare result against a benchmark treatment in which subjects shop twice with no labels. Labels include the existing Multiple Traffic Lights, Reference Intakes and Health Star Rating, and two newly proposed designs: NutriScore, a 5-color synthetic label, and SENS, a frequency-based recommendation label. We measure nutritional quality using the FSA score. All labels but Reference Intakes significantly improve nutritional quality. NutriScore is significantly more effective than all other labels, followed by the Australian Health Star and Multiple Traffic Lights. The nutritional improvements due to the labeling come at an economic cost, as the average cost of 2000Kcal increases for all labels. Nonetheless, we show that the extra cost for a unit nutritional improvement is borne mainly by richer households. Behaviorally, change is concentrated in the extremal categories of each label. Easier to understand labels have a higher impact and crowd out more successfully other information cues like ingredients lists and nutritional tables.