Generally speaking, meat production in the United States is produced in an environmentally unsustainable manner. An important personal rationale for sticking to a mostly vegetarian diet is that it reduces by some small amount demand for meat production processes that generate a large amount of greenhouse gas emissions and fertilizer runoff, and that demand pumping antibiotics into cows and pigs housed in feedlots. I do eat some meat occasionally; I don’t mind that other people eat lots of it; and I’m fully aware that my income and living situation allow me to make this choice. But a recent policy forum in Science presents some compelling research-based arguments for why there’s a lot of variation in the environmental impact of raising animals for slaughter:
However, the argument that all meat consumption is bad is overly simplistic. First, there is substantial variation in the production efficiency and environmental impact of the major classes of meat consumed by people (Table 2). Second, whilst a substantial fraction of livestock is fed on grain and other plant protein which could feed humans, there remains a very significant proportion which is grass-fed. Much of the grassland used to feed these animals could not be converted to arable, or could only be converted with significant adverse environmental outcomes. In addition, pigs and poultry are often fed on human food “waste.” Third, through better rearing or improved breeds it may be possible to increase the efficiency with which meat is produced. Finally, in developing countries meat represents the most concentrated source of some vitamins and minerals, which is important for individuals such as young children. Livestock also are used for ploughing and transport, provide a local supply of manure, can be a vital source of income and are of huge cultural significance for many poorer communities.
The whole piece is dense, but worth a read for foodies and anyone involved in a whole swath of disciplines from energy and environmental policy to human rights and foreign relations, as it takes a close look at the challenge of feeding everyone on the planet as the population increases, but more importantly, as populations grow wealthier and has more resources to buy pricier foods, including meat. So kudos to Science for archiving this outside the pay wall.