An explorative assessment of environmental and nutritional benefits of introducing low-carbon meals to Barcelona schools.

Shifting to plant-based and low-carbon diets is a key measure for climate change mitigation. In this regard, national and local governments are setting goals and actions to tackle this issue. The municipality of Barcelona has set an intervention for the academic year 2020-21: introducing low-carbon meals in public schools. This study assesses the environmental and nutritional benefits of this intervention by applying the Life Cycle Assessment (LCA) methodology, with an energy and nutritional functional unit; and combined it with the Water-Energy-Food (WEF) nexus approach, by considering three WEF resources-based impacts (Blue Water Footprint (BWF), Primary Energy Demand (PED) and Land Use (LU)) and the Global Warming Potential (GWP). The transition to a low-carbon meal would reduce between 46 and 60% the environmental impacts. These benefits could even be higher when extra interventions within the school boundaries are applied. More research in behavioural change is needed in order to evaluate both: the acceptance of the new menus by scholars and the adaptation of the school kitchen staff to the new menu. Finally, it is suggested to monitor the environmental and nutritional changes of the introduction of low-carbon meals within the school menus in an integrated way.