The role of energy cost in food choices for an Aboriginal population in northern Australia

Objective: To explore the relationship between dietary quality and energy density of foods (MJ/kg) and energy cost ($/MJ) for an Aboriginal population living in a remote region of northern Australia. Design: For a 3-month period in 2005, we collected food and non-alcoholic beverage supply data from food outlets available to the study population. From these data, we compared the energy density of foods with their energy cost. Main outcome measures: Energy density and energy cost of food purchases. Results: The diet of the study population was high in refined carbohydrates and low in fresh fruit and vegetables. Foods with high energy density were associated with lower costs and contributed disproportionately to energy availability. Conclusion: The energy-cost differential between energy-dense, nutrient-poor foods and energy-dilute, nutrient-rich foods influences the capacity of Australian Aboriginal people living in remote communities to attain a healthy diet. This is consistent with the "economics of food choice" theory, whereby people on low incomes maximise energy availability per dollar in their food purchasing patterns, and has particular relevance for developing nutrition policy and strategies in Aboriginal communities, where poor nutrition is a major determinant of preventable chronic disease.