A Causal Loop Diagram for Understanding Systemic Complexity Around Nutrition Security in DC’s Wards 7 and 8

Background: Nutrition security is the ability to access, afford, prepare, and incorporate nutritious foods into daily life. Washington, DC’s Wards 7 and 8 have long experienced inequitable investment in food infrastructure, which is part of a complex place-based system, resulting in disparities in nutrition security and subsequent diet-related health outcomes. Methods: We worked with a Community Advisory Board composed of Wards 7 and 8 residents and practitioners across different sectors to map the complex system driving nutrition security in their community. Through a series of group model building activities, a causal loop diagram was synthesized by university researchers and presented back to the Community Advisory Board for feedback and edits. Results: The causal loop diagram (CLD) includes 26 variables and 11 highlighted feedback loops. The CLD spans individual healthy eating behavior, community norms, community ownership of food operations, and public policy. Discussion: The diagram provides a shared systems representation of the factors shaping nutrition security and identifies feedback structures and potential leverage points for collective action. We applied the social ecological model to analyze potential strategies for strengthening each level of feedback loops to promote healthy eating and achieve nutrition security.