Many people have committed themselves to a livestock-free diet. The primary reasons for doing this include ethics and health (animals are bred in captivity, forced to live in terrible conditions before being culled for production, and reducing red meat can help lower cholesterol and reduce heart disease). This article will address the environmental reasons why a livestock-free diet may be a good option.
Researchers from Bard College, Weizmann Institute of Science, and Yale University have studied the food industry to break down the resources and greenhouse gas (GHG) emissions from cattle, pork, poultry, laying hens, and some crops.1 All data was collected from 2000 to 2010 and values are standardized across the food categories based on number of calories.
Figure 1 shows a graphical comparison for the resource (land and water) requirements and GHG pollutants for the cattle, pork, poultry, egg and crop industries.1,2 The results across the board for pork, poultry, and eggs are comparable, within a factor of 2; however beef production requires 28 times more land, 11 times more water, and produces 5 times more GHG compared to any other meat industry.1 Also reported for plant food production is data to suggest the crop industry requires and produces 2 to 6 times less land, water and GHG compared to pork, poultry and eggs.1 It should be noted that the authors acknowledge the difficulty in acquiring some of this data could result in some error. However, it should be easy to see the massive impact of the beef industry despite possible errors.
Beef cattle are also one of the biggest producers of GHG due to their rumen, or large “fore-stomach”, where microbials ferment food for digestion and produce methane, says the EPA.3 Due to their digestive process, the GHG produced by all livestock is about 386 gigagrams (Gg) of CO2 equivalents per day in the US, where cattle make up 96% of these emissions. In other words, the CO2 equivalent produced by cattle’s digestion is the same as burning 40 million gallons of gasoline per day. Pork is the next highest at 650 thousand gallons of gasoline in emissions and poultry produce less than 15 thousand gallons of gasoline worth of CO2 equivalents per day. To add a little perspective, the total amount of gasoline consumed in the US every day is about 350 million gallons and growing,4 and the agriculture sector only accounts for 10% of all greenhouse gas emissions (this includes industrial and methane produced through digestion) in the US.3
The goal of this article is to educate on the staggering environmental impact that the cattle industry has on the environment. While the best option for any sustainable scientist or conscientious consumer is to adopt a livestock-free lifestyle, the reduction or elimination of beef in a normal diet could be the next best thing.
1. Eshel, G.; Shepon, A.; Makov T.; Milo, R., Land Irrigation Water, Greenhouse Gas, and Reactive Nitrogen Burdens of Meat Eggs, and Dairy Production in the United States. Proceedings of the National Academy of Sciences of the United States 2014, 111, 11996-12001.
2. Nuwer, R., Raising Beef Uses Ten Times More Resources than Poultry, Dairy, Eggs or Pork. Smithosian Magazine 2014, smithonian.com
3. US GHG Inventory 2014 Chapter 6 Agriculture. Environmental Protection Agency 2014, epa.gov
4. How Much Gasoline does the United States Consume? (November 2014) eia.gov /tools/faqs/faq.cfm?id=23&t=10