Environmental Cost of Meat
- Aria Fox
- April 8, 2023
The U.S. could feed 800 million people with grain that livestock consume say Cornell University ecologist researchers. If the grain were exported, it would increase the U.S. trade balance by $80 billion per year.
The American system of feeding livestock grain rather than allowing cattle to feed on pastureland consumes resources far disproportionate to the yield. What’s more it accelerates soil erosion, uses huge amounts of water, and affects world food supply in a negative way.
Grass-fed livestock yields more than the recommended daily allowance (RDA) of meat and dairy protein. While it’s true that the protein yield of beef is greater than that achieved by high-protein plants in the human diet, it is only 1.4 times more nutritious in comparable amounts. And with the quantities the average American eats in a day, the protein yield is more than enough to meet the RDA.
According to animal production data that tracks use of fossil energy from the feed trough to the dinner table, broiler chickens provide the most efficient use of fossil energy—beef the least. Producing chicken meat consumes energy in a 4:1 ratio to protein output, whereas the ratio is 54:1 for beef. Mutton is nearly as inefficient at 50:1.
Animal agriculture is a leading user of water resources in the U.S. For every kilogram of meat produced by grain-fed beef production, 100,000 liters of water are required, Chickens take dramatically less to make a kilogram of meat: 3500 liters of water per kilogram. In contrast, soybean production uses only 2000 liters. Potatoes require 500 liters.
With severe water shortages in the Western and Southern U.S., the situation is rapidly worsening as the growing population needs more and more water to meet its needs—not only urban users, but also farmers and ranchers.
Facts
Livestock are responsible for much of the soil erosion in the U.S. Soil loss averages 13 tons per hectare annually on lands where grain feed is produced. Pasture lands erode, too, but at half the pace: 6 tons per hectare annually.
The 7 billion livestock in the U.S. eat five times as much grain as the entire population.
On the average, animal protein production in the U.S. uses 28 kcal for every kcal of protein produced for human consumption. Beef and mutton are the most costly in terms of fossil fuel energy input to protein output (54.1 and 50.1, respectively).
U.S. farms and ranches account for 87 percent of all fresh water used each year. While livestock directly consume only 1.3 percent of that water, when the water for forage and grain is included, the water use figure rises dramatically. Every kilogram of beef uses 100,000 liters of water compared with 900 to produce a kilogram of wheat.
The U.S. produces almost 7 million tons of animal protein per year, enough to supply every American man, woman, and child with 75 grams per day The RDA of protein for a mixed diet—meat and plant sources combined—is 56 grams per day.
If all the grain now fed to livestock in the U.S. were exported and ranchers switched to grass-fed beef, the average American diet would drop from 75 to 29 grams of protein per day. That plus levels of average plant-protein consumption would yield more than the RDA for adults.
