As a mixed meat eating and vegetarian household we quite frequently debate the ethics of food and food production, not in an attempt to convert each other but because putting aside the ethical motivations surrounding the eating of meat, both forms of ‘diet’ create a demand on the planet, and both have the capacity to unsustainable. Recently one such discussion had us posing the question that assuming the very best current practices regarding environment protection and ethical treatment of animals were being adhered to then as a source of protein, which is more environmentally costly; dairy products such as milk and cheese, or eggs and meat from chickens?
There are so many variables at play in the production of diary versus poultry protein that I was glad I stumbled across an interesting piece of research the performed by the Environmental Working Group. They looked at the lifecycle total of greenhouse gas emissions for common protein foods and vegetables and expressed them as kilograms (kg) of carbon dioxide equivalents per kg of food product. Unsurprisingly the production of lamb meat and beef sat at the top of the pile producing 39kg and 27kg of carbon respectively per one kg of product. It also came as no surprise that lentils sat at the opposite end producing 0.9kg per one kg of product. What did surprise me though was where diary sat in relation to poultry.
Eggs generate 4.8kg of carbon per kg of food and chicken meat sits around 6.9kg of carbon per kg of food. Milk came in at an impressive 1.9kg and in fact creates less of a carbon footprint than broccoli at 2kg and potatoes at 2.9kg per kg of food. But what of cheese? With a whooping 13.2kg of carbon per one kg of food produced it ranks amongst the highest in terms of carbon footprint when analysing the common protein foods sitting above pork, turkey and fish. Needless to say this threw up all manner of side debates but it does serve to illustrate that things are not always as they might appear.