WASHINGTON - While modern cars are getting lighter, drivers are getting heavier - and America's fuel economy may be feeling the weight.
The Department of Energy says an extra 100 pounds lowers a vehicle's mpg capacity by up to 2 percent.
Automakers are using less steel and lighter plastics to reach higher fuel standards, but more than a third of adults are obese and that number is expected to increase.
The issue is already a concern for the airline industry, which says it used 350 million more gallons of fuel in 2000 than in 1990 because it was hauling more weight.
WTOP's Richard Day contributed to this story. Follow WTOP on Twitter.
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