Agricultural Economics Department


Date of this Version



CORNHUSKER ECONOMICS, University of Nebraska–Lincoln Extension, April 23, 2014


Copyright 2014 University of Nebraska


In an effort to broaden the focus of sustainability research from work on sustainable production that aims to influence farmer decisions when producing food, to research about sustainable consumption that aims to influence consumer decisions when buying food, we embarked on a research project that looks at environmental and health impacts of dietary choices. In this article, results from some initial work on the environmental impact are reported. Specifically, the energy efficiencies and consequent carbon emissions of the average United States, Japanese, Mediterranean, French and Nordic diets are compared. To put the results in perspective, the carbon emissions were converted into equivalent driving miles. Figure 1 (on next page) presents the composition of the average French, Japanese, Mediterranean, Nordic and U.S. diets in 2009, measured in kilocalories (kcal). The red and green areas represent the animal-based kcal and the plantbased kcal, respectively. The total amount of kcal consumed is at the top of each bar. The average U.S. diet contains the most calories (3,688/kcal/capita/day), though the Mediterranean and French diets represent similar consumption levels. With the exception of the average Japanese diet (2,723/kcal/capita/day), the rest of the diets are all above 3,000 kcal. The energy efficiency, defined as the ratio of the amount of energy in a food to the amount of energy required to produce the food for each of the five diets, was calculated using data from Pimentel and Pimentel (2008) and the U.S. Department of Agriculture (2013). We found that the most energy efficient diet is the Mediterranean diet, followed by the Japanese, U.S., French and Nordic diets (see Table 1, first numeric column, on next page).