To produce one kcal of protein in form of beef and eggs requires about 40 fossil fuel calories
To produce one kcal of protein in form of beef and eggs requires about 40 fossil fuel calories. (eggs 39, beef 40) [Below: from table 2, page 3, "Animal production in the United States and the fossil energy required to produce 1 kcal of animal protein Ratio of energy input to protein output"] Lamb: 57:1 Beef: 40:1 Eggs: 39:1 Swine: 14:1 Milk: 14:1 Turkeys: 10:1 Broilers: 4:1
David Pimentel and Marcia Pimentel, "Sustainability of meat-based and plant-based diets and the environment," American Journal of Clinical Nutrition, 2003 78: 3 660S-663S. http://ajcn.nutrition.org/content/78/3/660S.full [verified 4/15/14]