Fat Americans and energy usage

From Mother Jones:

Nineteen percent of US energy usage—about as much as is used to fuel our cars—is spent growing and delivering food to the average American who consumes 2,200 pounds of food a year. That's a whopping 3,747 calories a day—or 1,200 to 1,700 more than needed for personal or planetary health. The skinny truth is that as much as 7.6 percent of total energy in the United States today is used to grow human fat, fat that translates to 3,300 pounds of carbon per person.

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For starters, half of our food energy use comes from producing and delivering meat and dairy. If we gave up just meat, we could maintain that hefty 3,747-calorie intake but consume 33 percent less in fossil fuels doing it. If Americans cut just one serving of meat a week, it would equal taking 5 million cars off the road.

One-third of those 3,747 daily calories comes from junk food—potato chips, soda, etc. We can save on fossil fuel costs in this area by installing more efficient lighting, heating, and cooling in the plants that make the stuff and by using less packaging materials. But we'd save a lot more if you and I simply bought less of it. A can of diet soda, for instance, delivers only 1 calorie of food energy at a cost of 2,100 calories to make the drink and the can. Transporting the components and the finished product costs even more, and shipping processed food and its packaging accounts for much of the problem of America's food averaging 1,500 travel miles before it's eaten.