E, the respected environmental magazine, noted in 2002 that more than one-third of all fossil fuels produced in the United States are used to raise animals for food. This makes sense, since 80 percent of all agricultural land in the U.S. is used by the meat and dairy industries (this includes, of course, the land used to raise crops to feed them).
Simply add up the energy-intensive stages: (1) grow massive amounts of corn, grain, and soybeans (with all the required tilling, irrigation, crop dusters, and so on); (2) transport the grain and soybeans to manufacturers of feed on gas-guzzling, pollution-spewing 18-wheelers; (3) operate the feed mills (requiring massive energy expenditures); (4) transport the feed to the factory farms (again, in inefficient vehicles); (5) operate the factory farms; (6) truck the animals many miles to slaughter; (7) operate the slaughterhouse; (8) transport the meat to processing plants; (9) operate the meat-processing plants; (10) transport the meat to grocery stores; (11) keep the meat refrigerated or frozen in the stores, until it's sold. Every single stage involves heavy pollution, massive amounts of greenhouse gases, and massive amounts of energy.
Most of us turn off the lights when we leave a room and attempt to conserve energy in other ways, but eating meat is the most inefficient and resource-intensive thing we do. If we Americans cut our meat consumption, our oil problems would be drastically reduced.