Dollar General, Dollar Tree, Family Dollar and other dollar stores are chock full of cheap, highly processed foods -- just the sort of eats that can lead to obesity, heart disease and other health problems. But dollar store shoppers are surprisingly savvy, and the foods sold in these discount stores don't appear to be doing drastic harm to Americans' overall diets , researchers reported Aug. 11 in the Journal of the Academy of Nutrition and Dietetics . The total number of household calories