According to German researchers, the food miles concept misleads consumers because the size of transportation and production units is not taken into account. Using the methodology of Life Cycle Assessment (LCA) in accordance with ISO 14040, entire supply chains providing German consumers with food were investigated, comparing local food with food of European and global provenance. Large-scale agriculture reduces unit costs associated with food production and transportation, leading to increased efficiency and decreased energy use per kilogram of food by economies of scale. Research from the Justus Liebig University Giessen show that small food production operations may cause even more environmental impact than bigger operations in terms of energy use per kilogram, even though food miles are lower. Case studies of lamb, beef, wine, apples, fruit juices and pork show that the concept of food miles is too simple to account for all factors of food production.