The average weight of an American adult has increased 24lbs since 1960. That additional weight costs the airlines money as hauling extra weight takes more fuel. At around $3 per gallon of jet fuel, the 24 extra pounds translates into about 175 million gallons of add’l fuel, costing over $500 million per year.
How about cars? For every additional average pound of passenger weight in a car, 39 million extra gallons of gasoline are consumed in the US during the year. Given the 24 pounds of additional average weight, that translates into about a billion gallons of extra fuel consumed a year.