In a recent article in the American Journal of Clinical Nutrition, authors A. Drewnowski and S. E. Specter review the relationship among energy density, energy costs, and the rising tide of obesity. Their conclusion that poverty may play a role in the development of obesity is based on the following 4 tenets: populations with the least education and greatest incidence of poverty have the highest rates of obesity. Food with the highest energy density (MJ/kg) often have the lowest energy cost ($/MJ) or, put another way, high-calorie foods are less expensive to purchase than those of lower calorie levels. Because many of these high-energy foods are composed of refined grains, added sugars, and fats, they are often extremely palatable and are consumed in greater quantities, leading to increased calorie intake. Finally, those at the lower end of the economic spectrum spend less for food, have lower fruit and vegetable intakes, and have lower quality diets. Based on computer modeling, reducing available finances produced a diet of high-fat energy-dense foods similar to those consumes by low-income groups. (American Journal of Clinical Nutrition, 2004;79:6-16.)