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

BACKGROUND: Hospital canteens provide an effective setting to improve users' dietary habits. The study evaluates users' food choices-considering nutritional composition and environmental impact -after an educational and environmental intervention, comparing the results with pre-intervention choices. METHODS: A pre-post intervention study was conducted in three hospital canteens (C1, C2, C3) in northeastern Italy, during two index weeks in September 2022 (T0) and 2023 (T1). Canteen users were recruited before and after an intervention consisting of posters on healthy eating, descriptive norm messages, and environmental changes regarding fruit and vegetables. Photos of participants' lunch trays were collected, and food choices were analyzed for nutritional composition and sustainability. Descriptive statistics and appropriate non-parametric and chi-square tests were used to compare outcomes between assessment periods and across canteens. 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 fiber value fell within the reference 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 g CO2eq. to 1,227 g CO2eq. 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.