'Obese' drivers use up more petrol, says study

Americans are spending more on petrol because they are getting fatter, according to a new study.

Cars in the US are using about a billion gallons more fuel annually than they would be if drivers weighed the same as they did in 1960, the Washington Post reported.

Adults are now an average of at least 24 pounds heavier than they were then.

At recent petrol prices in the US that means 2.2 billion dollars are 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," study co-author Sheldon Jacobson, a professor at the University of Illinois at Urbana-Champaign, told the newspaper.

The average man in the US weighs 13 stone 9 pounds, 25 pounds more than in 1960, while the average woman weighs 11 stone 10 pounds, up 24.

Prof Jacobson, an industrial engineer, calculates that Americans could save enough fuel to run 1.7 million vehicles for an entire year simply by trimming down to the size of the 1960 counterparts.

"What we have here is a socio-economic implication of obesity," he said.

"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 is due to be published in the journal Engineering Economist.