Sustainability and nutritional composition of food choices in hospital canteens: a pre-post intervention study

Background: Hospital canteens provide an effective setting for improving the dietary habits of users. The study evaluates the food choices of users after an educational and environmental intervention, considering nutritional composition and environmental impact, and to compare the results with pre-intervention choices. Methods: A cross-sectional study was conducted in three hospital canteens (C1, C2, C3) in northeastern Italy, during two index weeks in September 2022 (T0) and 2023 (T1). An intervention was introduced between T0 and T1, consisting of posters on healthy eating, descriptive norm messages, and environmental changes regarding fruit and vegetables. Photos of lunch trays were collected, and choices were analyzed for nutritional composition and sustainability. Results: 2,851 trays were analyzed: 1,227 at T0 (798 in C1, 228 in C2 and 201 in C3) and 1,624 at T1 (1,005 in C1, 348 in C2, 271 in C3). In C1 and C3, there was an increase in median energy (+30 kcal; +135 kcal) compared to pre-intervention meals, while in C2 there was a decrease (-118 kcal). Despite a slight improvement in macronutrient composition, at T1 meals in all canteens were still high in lipids (30%E; 39%E; 35%E) and low in carbohydrates (44%E; 39%E; 41%E). The fibre value fell within the recommended range only in C1 and C3. The median carbon (CF) and water (WF) footprints of meals in all canteens remained high: at T1 CF ranged from 966 gCO2eq. to 1,227 gCO2eq. and WF from 1,025 L H2O to 1,207 L H2O. Conclusion: The intervention has led to partial improvements in food choices. To achieve more significant results, it may be necessary to implement a parallel intervention on food offer.