Abstract

In this article, we explore the relationship between dietary composition, on-farm energy use, and CO2 emissions. Then, we estimate the cost of these emissions for the US diet relative to a Japanese, Greek, French, or Finnish diet. To carry out the analysis, we use four main data inputs: the proportions of per-capita caloric intake from plant-based and animal-based products for each diet, the products’ energy efficiencies, CO2 emissions per calorie, and total calories. We consider two scenarios: one in which dietary composition varies and the second in which both composition and calories vary with the respective levels in each diet. Our findings suggest that a shift to the Greek diet reduces CO2 emissions by 5.5 percent when daily caloric intake stays at the US level. This result suggests that the types of animal products being consumed matter, not just the amount, since the Greek diet has a higher proportion of animal-based products than the Japanese diet. When US daily caloric intake varies, the Japanese diet is the least polluting and reduces CO2 emissions by 29.2 percent due to the relatively fewer calories consumed in the Japanese diet. Alternatively, the French and the Finnish diets have a higher share of animal-based products and produce more CO2 emissions in both dietary scenarios. The social cost of the CO2 emissions associated with producing the current US diet ranges from $4.51 to $90.27 per capita, or 0.48 percent to 9.53 percent of farm cash receipts. Switching to either the Greek or the Japanese diet would result in lower costs in both of the scenarios we consider whereas the French and Finnish diets increase the social cost of CO2 emissions.