Why is food insecurity associated with health outcomes? A review of possible pathways

Food insecurity (FI) has become a major focus of academic and policy concern. FI is prevalent even in high-income countries, and is consistently associated with poor physical and mental health outcomes. These associations are attenuated but not eliminated by controlling for more general social determinants. Though it is clear that the associations exist, it is less clear why. FI reflects social and material disadvantage, so its negative association with health is not a surprise; but there are multiple pathways by which the association could play out. We review four: (A) FI is a non-causal correlate of general disadvantage; (B) FI causes poor health, but this is not mediated by diet; (C) FI causes poor health by changing what people eat; (D) FI causes poor health by changing the temporal patterning of their eating. These pathways are not mutually exclusive, and we suggest that several play partial roles. Understanding their relative importance is nonetheless an important goal if we wish to intervene effectively to mitigate the health burden of FI.