Nutri-Score, multiple traffic light and incomplete nutrition labelling on food packages: Effects on consumers' accuracy in identifying healthier snack options

Front-of-package (FOP) nutrition labels are designed to help consumers evaluate the healthiness of foods and to promote healthier food choices. In this study, an online experiment with Swiss consumers (N = 1313) was conducted to compare the effects of different nutrition label formats on consumers' evaluations of snack food healthiness. Participants were asked to select the healthier option in 105 pairwise comparisons of 15 salty snacks. The participants were randomly assigned to one of five conditions: the FOP presented with (1) the nutrition facts table, (2) the multiple traffic light (MTL), (3) the Nutri-Score, (4) the Nutri-Score on half of the products, or (5) no nutrition information (control). The consumers' evaluations of the snacks' healthiness were fairly accurate, even without being given nutrition information on the packaging. The Nutri-Score led to the greatest accuracy in identifying the healthier of two snacks (when using the British FSA/Ofcom nutrient profiling score to determine product healthiness); however, this had only a minimal effect on the evaluation when only some of the products were labelled. Both FOP labels were superior to the FOP with and without the nutrition facts. This indicates that for maximum effectiveness, the labelling of all available products is needed. The perceived usefulness and public support of mandatory implementation were higher for the MTL than for the Nutri-Score label; however, for the latter, perceived usefulness and public acceptance were higher among the participants who became familiar with the label during the experiment than among those who did not.