Navigating the syndemic: a socio-psychological approach to food security and responsible consumption in low-income populations.

Global food security is currently a priority, especially amid a "grim regression" that is undermining efforts to eradicate malnutrition by 2030. This perspective argues that the current crisis is not merely a supply chain disruption but a syndemic convergence where biological threats and economic instability interact to erode consumer agency. We posit that vulnerable populations are forced into a "lethal calculation," prioritizing immediate caloric survival over food security and long-term health, thereby becoming trapped in cycles of ultra-processed food consumption. To address this, we challenge the limitations of purely rational economic models and propose an integrated psychological framework that combines the Theory of Planned Behavior (TPB) and the Health Belief Model (HBM). This integration accounts for the specific "internal determinants" and "perceived threats" that drive decision-making in high-stress, low-income environments to achieve food system sustainability. Unlike previous studies that primarily apply the TPB and HBM to predict individual choices, this perspective uses their integration to propose a structural reorientation of food systems. We introduce the concept of "reverse-designed food systems" as a conceptual bridge that aligns system architecture with the cognitive and behavioral constraints of consumers in high-stress environments. This approach shifts the focus from production-led efficiency to a consumer-centric structural design, where the system infrastructure assumes the cognitive load traditionally borne by individuals living in poverty.