Weight puts a strain on fuel economy

CHICAGO — Want to spend less at the pump? Lose some weight.

That’s the implication of a new study that says Americans are burning nearly 1 billion more gallons of gasoline each year than they did in 1960 because of their expanding waistlines. Simply put, more weight in the car means lower gas mileage.

Using recent gas prices of $2.20 a gallon, that translates to about $2.2 billion more spent on gas each year.

“The bottom line is that our hunger for food and our hunger for oil are not independent. There is a relationship between the two,” said University of Illinois researcher Sheldon Jacobson, a study co-author.

“If a person reduces the weight in their car, either by removing excess baggage, carrying around less weight in their trunk, or yes, even losing weight, they will indeed see a drop in their fuel consumption.”

Outside experts said that even if the calculation aren’t exact, the study makes sense.

“If you put more weight into your car, you’re going to get fewer miles per gallon,” Emory University health care analyst Kenneth Thorpe said Wednesday.

The same effect has been seen in airplanes. Research from the Centers for Disease Control and Prevention found that heavy fliers have contributed to higher fuel costs for airlines.

The obesity rate among U.S. adults doubled from 1987 to 2003, from about 15 percent to more than 30 percent. Also, the average weight for American men was 191 pounds in 2002 and 164 pounds for women, about 25 pounds heavier than in 1960, government figures show.

The study’s conclusions are based on those weight figures and Americans’ 2003 driving habits, involving roughly 223 million cars and light trucks nationwide.