Numerous food assistance programs (FAP) aim to ensure food security among low-income American households. However, the literature suggests that participation in food assistance programs may be associated with the US childhood obesity epidemic. The goal of this study is to analyze the association between the number of major food assistance programs children participate in and childhood obesity. The major food assistance programs considered are the Supplemental Nutrition Assistance Program (SNAP), the Special Supplemental Food Program for Women, Infants, and Children (WIC), the National School Lunch Program (NSLP), and the School Breakfast Programs (SBP). This is the first study to consider the relationship between childhood obesity and participation in four key food assistance programs in the United States. National Household Food Acquisition and Purchase Survey (FoodAPS) data are analyzed using both mean comparison tests and probit regression analysis. We find an inverse association between the number of food assistance programs a child participates in and childhood obesity. Outcomes from this study can help improve policies aimed at supporting the well-being of low-income children. Overall results suggest that policymakers should prioritize enrolling children in all the food assistance programs for which they are eligible in order to have the greatest impact on childhood obesity.