To Spend Less On Gas, Lose The Spare Tire

By Christopher Lee
Washington Post Staff Writer
Thursday, October 26, 2006

A little belt-tightening could really help Americans save on gas.

Americans are spending more money on fuel these days in part because adult men and women on average are at least 24 pounds heavier than their counterparts were in 1960, a study has found.

Collectively, today's automobiles are burning more gasoline to haul all that extra weight around -- about 1 billion gallons more annually, in fact, than they would if drivers weighed the same as they did in 1960. At recent gas prices of $2.20 a gallon, that adds up to $2.2 billion more spent at the pump each year because of America's weight problem.

"What we have here is a relationship that exists between the obesity epidemic and fuel consumption," said Sheldon H. Jacobson, a professor at the University of Illinois at Urbana-Champaign and a co-author of the study. "Now, does it mean we should all go out and lose weight? Of course not. But it does mean that there is a relationship and we should be aware of it."

The analysis says nothing about the improvements in fuel economy in vehicles since 1960, Jacobson said. It merely looks at how fuel consumption would be different in today's vehicles if drivers weighed less.

The average man weighs 191 pounds, 25 more than in 1960. The average woman weighs 164 pounds, up from 140 in 1960.

The extra 1 billion gallons of gas that their cars are burning because of the added weight amounts to about three days' worth of fuel for the 225 million cars, light trucks and SUVs in the United States. Each pound gained by the average person collectively leads to the consumption of 39 million extra gallons of fuel a year, the study found.

Looked at another way, Americans could save enough gas to fuel 1.7 million vehicles for an entire year simply by shedding enough pounds to be as svelte as the Americans of 1960, Jacobson said.

So losing weight could promote fuel conservation and help the environment, as well as bring the more familiar benefits of better health.

"What we have here is a socioeconomic implication of obesity," said Jacobson, an industrial engineer. "If people decide as a nation to get healthier and lose weight and be fitter, not only will we have a healthier country but we're actually going to reduce our dependence on foreign oil very covertly, simply because we're going to be using less."

The study will appear in the October-December issue of the Engineering Economist, a peer-reviewed journal.

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