This study examines the impact of preventive care strategies on obesity prevalence and associated healthcare expenditures in the United States using system dynamics modeling. Obesity is a multifaceted public health challenge involving interdependent behavioral, biological, economic, and systemic factors that interact nonlinearly and evolve, which are characteristics of a complex system. To better understand these dynamics, we developed causal loop diagrams (CLDs) based on a rapid literature review, which mapped the feedback structures among key variables, including dietary behavior, physical activity, healthcare access, and the progression of obesity-related illnesses. The resulting CLDs identify both reinforcing and balancing feedback loops that govern transitions across population health states (healthy, pre-obese, obese, and chronically ill), as well as resource allocation dynamics within the healthcare system. This study makes a unique contribution by developing a comprehensive conceptual model that maps preventive care strategies using system dynamics feedback structures. Unlike prior models that focus narrowly on either physiological or behavioral factors, our model integrates multi-level pathways – behavioral, clinical, and economic – highlighting leverage points for policy intervention. The model reveals leverage points where upstream interventions, such as improving dietary behavior or increasing access to primary care, may disrupt harmful cycles and reduce long-term healthcare costs. These findings offer policymakers a systems-oriented perspective on where and how to intervene to curb the obesity epidemic and its associated economic burden. |