Polychrome versus monochrome Nutri-Score shelf labels: An eye-tracking study of consumer attention and choice

Amid rising global obesity and growing attention to nutrition, front-of-pack labels like the Nutri-Score have become essential tools for guiding healthier consumer choices. While its traffic light color coding enhances comprehensibility, Nutri-Score visibility varies in practice, particularly in Germany, where price tag labels may appear in monochrome. This study examines how additional Nutri-Score price tag labels – displayed in either polychrome or monochrome – affect consumers' visual attention and product choice in a simulated supermarket setting compared to the standard polychrome front-of-pack label. A total of 199 German adults were assigned to one of four conditions: polychrome double label, monochrome double label, polychrome single label (standard), or no label (control). Eye-tracking technology measured gaze behavior, followed by an on-site questionnaire. Findings indicate that polychrome Nutri-Score labels attracted statistically significant more fixations than monochrome versions. Exposure to any additional Nutri-Score label increased visual attention, with color-enhanced versions proving more effective. Especially, the increase in visual engagement on Nutri-Score labels A and C correlates with a corresponding product choice. These results underscore the critical role of label design in effective nutrition communication. Increasing label visibility through strategic placement and color enhances visual attention and facilitates more informed decision-making at the point of sale. Polychrome Nutri-Score labels integrated into retail shelf tags enable consumers to compare the nutritional quality of products more effectively than less noticeable monochrome labels. Therefore, the use of color-coded ratings should be prioritized to maximize label effectiveness and promote more informed dietary choices.