概要
Organically produced food is often considered more environmentally friendly than conventionally produced food, and Germany is one of the most important and rapidly growing markets for organic food in Europe. However, the carbon footprints and land use of organic diets, and how they compare to conventional diets, have not yet been quantified. Using food consumption data from the German National Nutrition Survey II and carbon footprint and land-use data from life cycle assessment studies of conventional and organic food products, carbon footprints and land use of conventional and organic diets in Germany were calculated for three consumer categories: men, women and their combined unweighted average. Conventional diets are defined as the average diet of consumers who do not buy organic food products; organic diets are the average diets of consumers whose food purchases include a large share of organic food products. Greenhouse gas emissions associated with land use change are not included. The carbon footprints of the average conventional and organic diets are essentially equal (ca. 1250 CO2-eq cap(-1) year(-1)), while the land use to provide food is ca. 40% greater in the organic diet (ca. 1900 and 2750 m(2) of land cap(-1) year in the conventional and organic diets, respectively). The average conventional diet contains 45% more meat than the average organic diet, which on the other hand contains 40% more vegetables, fruits, and legumes (combined). Animal-based food products dominate the carbon footprints and land use (ca. 70-75%) in both diets. The organic diet, in particular that of women, is more aligned with health-based dietary guidelines. Diet-related carbon footprints and land use can be reduced by shifting toward diets with less animal-based food products (other measures are also discussed). General conclusions about the overall performance of conventional and organic agriculture are not supported by this study since only carbon footprints and land use were assessed, while other important issues, such as biodiversity, ecotoxicity impacts and animal welfare, were not considered. (C) 2017 Elsevier Ltd. All rights reserved.