1. •• Hiza HAB et al. Diet quality of Americans differs by age, sex, race/ethnicity, income, and education level. J Acad Nutr Diet. 2012;113(2):297–306. This study used the Healthy Eating Index-2005, a measure of diet quality in terms of conformance to the 2005 Dietary Guidelines for Americans, to describe the diet quality of Americans by varying sociodemographic characteristics in order to provide insight as to where diets need to improve.
2. •• U.S. Department of Agriculture and U.S. Department of Health and Human Services, Dietary Guidelines for Americans, 2010. Washington, DC: U.S. Government Printing Office; 2010. Based on the most recent scientific evidence review, this document provides information and advice for choosing a healthy eating pattern—namely, one that focuses on nutrient-dense foods and beverages, and that contributes to achieving and maintaining a healthy weight. By law, Dietary Guidelines for Americans is reviewed, updated if necessary, and published every five years. It is jointly created by the US Department of Agriculture and the US Department of Health and Human Services.
3. Christian T, Rashad I. Trends in US food prices, 1950–2007. Econ Hum Biol. 2009;7(1):113–20.
4. Kuchler F, Stewart H. Price Trends Are Similar for Fruits, Vegetables, and Snack Foods. Economic Research Report 55. Economic Research Service, U.S. Department of Agriculture; 2008.
5. Lakdawalla D, Philipson T. The growth of obesity and technological change: a theoretical and empirical examination. National Bureau of Economic Research; 2002.