Everybody eats. And consumers increasingly try to consider the environmental effects of their food choices. For example, if you want to eat meat, how do your choices compare? That’s what a group of researchers set out to discover. And they found that raising one animal is dramatically more environmentally draining than all the others: cows. The research is in the Proceedings of the National Academy of Sciences. [Gidon Eshel et al., Land, irrigation water, greenhouse gas, and reactive nitrogen burdens of meat, eggs, and dairy production in the United States]
The scientists noted the challenge in accessing data and creating metrics that can be compared across livestock and to potato, wheat and rice production. They settled on national data from the U.S. Departments of Agriculture, the Interior and Energy. The team calculated the production costs by assessing land area, water needs and fertilizer. They also analyzed greenhouse gas emissions.
Producing pork, poultry, eggs and dairy were between two and six times less efficient than growing potatoes, wheat and rice. And in the current agricultural system, beef uses 28 times more land, 11 times more water and 6 times more fertilizer than the average of the other categories of livestock. Cattle ranching also creates five times more greenhouse gas emissions.
The researchers hope this data will help consumers make informed choices and policy makers create systems that can reduce the environmental costs of what we eat.
—Cynthia Graber
