People Of Higher Socioeconomic Status Choose Better Diets, But Pay More Per Calorie

http://www.sciencedaily.com/releases/2009/05/090501090927.htm

ScienceDaily (May 4, 2009) — As people become more educated, studies have demonstrated that they tend to choose foods that are lower in calories but higher in nutrients. They also pay more. Researchers from the University of Washington have now compared the eating habits and food costs of a sample of 164 adults in the Seattle, Washington area.
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The energy density of the diet (i.e. available energy per unit weight) is one indicator of diet quality. Lean meats, fish, low-fat dairy products and fresh vegetables and fruit provide fewer calories per unit weight than do fast foods, sweets, candy and desserts. Energy dense foods provide more calories per unit weight but tend to be nutrient-poor.