Food insecurity is linked to a multitude of adverse health outcomes in adults and children. Yet, access to Medicaid has been shown to reduce such adverse health outcomes, and therefore, the ability to access medical care, specifically via Medicaid, is conceivably a driving factor behind the association between food hardship and adverse health. This study has three specific research aims: (1) estimate the effect of Medicaid enrollment on child and household measures of food insecurity; (2) estimate the effects of the Supplemental Nutrition Assistance Program (SNAP) on food insecurity; and (3) estimate dual-enrollment effects of Medicaid and SNAP on food insecurity. The study will use secondary, observational data combined with state-level policies and implement a quasi-experimental Instrumental Variable design. The study sample will be representative of U.S. households with children headed by an individual between the ages of 19 and 64. Main outcome measures are household food security status and child food security status.