Nudging Healthier and More Sustainable Eating Habits in University Cafeterias: The FOOD-HACK Project.

Background/Objectives: The global syndemic of obesity, undernutrition, and climate change highlight the complex health and environmental challenges faced by young adults. These challenges may intensify during the transition to university. As a matter of fact, limited budgets, time constraints, and insufficient culinary skills often lead to unbalanced diets and increased risk of obesity. University cafeterias, serving large numbers of students, represent an ideal setting to promote healthier and more sustainable eating behaviors. The FOOD-HACK Project aimed to design and implement a cafeteria-based intervention using nudging strategies to promote healthier and more sustainable lunch choices among university students. Methods: This pilot study employed a pre-post design with two independent phases in the Polo Cravino cafeteria at the University of Pavia. Food consumption was assessed over 12 non-consecutive days across four weeks. During the intervention, three nudging strategies were implemented: (1) choice architecture, (2) salient labeling, highlighting healthy and sustainable options, and (3) educational prompts. Results: Across both phases, 2400 tray photographs were collected. Post-intervention, the proportion of trays aligned with the Harvard Healthy Eating Plate and EAT-Lancet Planetary Diet models increased, reflecting higher consumption of vegetables and fruit. Legume-based first courses increased; however, legumes did not substantially replace animal proteins as the main protein source, and meat remained predominant in second courses. Reductions in trays containing multiple carbohydrate sources were also observed. Conclusions: The nudging intervention improved overall meal quality, demonstrating that subtle environmental modifications can guide students toward healthier dietary choices, particularly by increasing fruit and vegetable intake. However, the persistent preference for animal proteins highlights the challenge of shifting protein consumption toward more sustainable sources. These findings suggest that nudging can be an effective tool to promote healthier and more balanced eating behaviors in university settings, though complementary strategies may be needed to foster substantial changes in protein choices.