Assessing the environmental sustainability of hospital diets using water footprint and food waste indicators

Purpose – The objective of this research is to assess the environmental sustainability of a weekly hospital diet in terms of water consumption and food waste generation. This assessment is crucial for identifying more environmentally sustainable diets based on the development of the water-food waste index (WFWI). Design/methodology/approach – This research evaluates the water footprint of hospital diets according to the Water Footprint Network (WFN) guidelines and their food waste generation by applying the mass-balance approach. Primary data on food consumption and waste quantities were obtained through waste analysis conducted in nine hospital facilities in Southern Italy. The questionnaire was administered to 3,408 patients over a three-year period (2021–2023). Findings – Plant-based ingredients, despite their higher environmental sustainability, are wasted more than animal-based foods, underscoring a trade-off between reducing water consumption and minimizing food waste. However, some food items can achieve both environmental sustainability and consumer acceptability. Lettuce (WFWI 5 1.15 L/kg) and carrots (WFWI 5 2.88 L/kg) present a better sustainable performance compared to spinach (WFWI 5 8.09 L/kg) or eggplants (WFWI 5 8.77 L/kg). In terms of animal-based products, parmesan (WFWI 5 24.24 L/kg) is a more sustainable alternative to scamorza (WFWI 5 114.40 L/kg), while pork (WFWI 5 59.57 L/kg) is preferable to veal (WFWI 5 154.32 L/kg) in designing hospital diets. Originality/value – In the healthcare sector, food waste takes on particular significance considering its economic, social and environmental implications, such as the loss of nutritional values, the waste disposal costs and the negative environmental impacts. Although the assessment of sustainable diets is largely investigated in terms of carbon emissions, scarce attention is given to its water consumption. This research represents an original analysis that estimates both water footprint and food waste generation in the healthcare sector and develops a composite indicator to integrate water footprint and food waste data.