(HOUSTON CHRONICLE) Allstate insurance company says overweight Americans are thwarting the auto industry’s efforts to improve fuel-efficiency by adding extra pounds to their lighter-weight cars.

The auto insurer says 1 billion gallons of gasoline were burned each year between 1960 and 2002 because of our growing waistlines, citing a report by Entrepreneur.com. Americans are weighing in 20 pounds heavier than they did in 1990.

For every additional 100 pounds, a vehicle’s fuel economy drops by as much as 2 percent, according to the U.S. Department of Energy.

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