Cornell Study: Old Food System Used Less Energy

Cornell Study: Old Food System Used Less Energy

August 19, 2008

How much energy we use to produce food could be cut in half if Americans
ate less and ate local foods, wolfed down less meat, dairy and junk
food, and used more traditional farming methods, says a new Cornell
study.

"We could reduce the fossil energy used in the U.S. food system by about
50 percent with relatively simple changes in how we produce, process,
package, transport, and consume our food," said David Pimentel,
professor emeritus of ecology and agriculture in the College of
Agriculture and Life Sciences at Cornell.

Pimentel's analysis, co-authored with five former Cornell undergraduates
who were in Pimentel's Environmental Policy course in 2006, is published
in the academic journal Human Ecology.

Pimentel says that about 19 percent of the total fossil fuel used in
this country goes into the food system -- about the same amount we use
to fuel cars. His analysis details how changes in the food system could
reduce energy.

For example, the researchers recommend:

*Eat less and cut down on junk food: To produce the typical American
diet requires the equivalent of about 500 gallons of oil per year per
person, says the study. Americans, on average, consume about 50 percent
more calories than recommended by the federal government for optimal
health and get one-third of their calories from junk food. Eating less
and cutting down on junk food would use significantly less energy,
considering all the processing, packaging, and transportation costs
saved.

*Eat less meat and dairy: We use 45 million tons of plant protein to
produce 7.5 million tons of animal protein per year, according to
Pimentel. Switching to a vegetarian diet, he says, would require
one-third less fossil fuel than producing the current animal-based
American diet.

*Eat more locally grown food: Food travels an average of 1,500 miles
before it is eaten. "This requires 1.4 times the energy than the energy
in the food," Pimentel said. A head of iceberg lettuce, for example,
which is 95 percent water, provides 110 calories and few nutrients.
Irrigating the lettuce in California takes 750 calories of fossil energy
and shipping it to New York another 4,000 calories of energy per head,
according to the analysis. Locally grown cabbage, on the other hand,
requires only 400 calories to produce and offers far more nutrients, not
to mention it can be stored all winter long.

*Use more traditional farming methods: Pimentel's team also shows how
using methods to reduce soil erosion, irrigation and pesticide use,
through such things as crop rotation, manure, and cover crops, could cut
the total energy now used in crop production.

The study's co-authors are Sean Williamson, Courtney Alexander, Omar
Gonzalez-Pagan, Caitlin Kontak and Steven Mulkey, all Cornell Class of
2007.