Drivers of Ultra-Processed Foods in Hospital Food Services: A Group Model-Building Study

Background: The increasing consumption of ultra-processed foods (UPFs) is concerning, given their negative impacts on environmental sustainability and human health. Evidence suggests a substantial presence of UPFs in health-promoting settings. However, the factors driving these procurement and service delivery decisions remain largely unexplored. Aim: To develop a conceptual model of the known and potential system drivers of UPFs in hospital food services. Methods: Dietitians from purposively sampled Australian hospitals participated. Group model-building workshops followed pre-established scripts from the system dynamics literature. A series of causal loop diagrams identifying drivers of UPF supply in hospitals was developed using model-building software. Primary and secondary drivers were derived inductively from participants and cross-checked against transcripts to produce the consolidated model. Results: The model presents six primary drivers (hospital menu and nutrition standards, food procurement and contracts, cost, standardisation for quality control, shelf life, and convenience) and nineteen secondary drivers that together explain the increased supply of UPFs in hospitals. Feedback loops were apparent, with drivers mutually reinforcing one another. Conclusions: Complex and interconnected drivers explain the increasing supply of UPFs in hospitals. Findings should inform future strategies to build sustainable food systems through improving food provision and reducing UPF supply in hospitals.