This dissertation consists of three essays on health, nutrition and food security programs. The research objectives include identification and explanation of the complex interrelationship between food insecurity, health and nutrition, and several food environment factors. More specifically, the socio-economic factors associated with government food-assistance programs and obesity/diabetes rates in the U.S. were analyzed in this study. The data included county-level observations taken primarily from the Food Environment Atlas and other secondary sources for 2006 and 2008. Poverty was the major determinant of food insecurity, health and nutrition issues, and the food environment. In the first essay, factors associated with obesity and diabetes were analyzed using county data throughout the U.S. The results suggest that local food structures are associated with reduced diet-related diseases; however, it is not a stand-alone solution to the problem. Other determining factors include education, diet, milk/soda price ratio, access to healthy food products, availability of recreational facilities, race/ethnicity, age, and poverty. In the second essay, household food insecurity as reflected in participation rates in the Supplemental Nutritional Assistance Program (SNAP) was analyzed at national and regional levels. County poverty rates and socio-economic indicators such as income levels, unemployment rates, education, and food deserts are explanatory factors associated with household food insecurity. National programs aimed at mitigating food insecurity rates are definitely helpful; however, a regional and more specialized approach tailored to the need of each area may improve responses to food insecurity. In the third essay, the analysis looks at food insecurity in children as it is manifested in National School Lunch Program (NSLP) participation rates. Median household income and unemployment rate are consistently significant explanatory variables of childhood food insecurity, before and during the recession, both at the national and regional models. Consistent with the results from the second essay, education, and food deserts are other factors associated with food insecurity in children.