Economics study links obesity to gasoline prices
A recent study by economics graduate student Charles Courtemanche found that higher gasoline prices in the United States could lower obesity.
Courtemanche’s dissertation, however, received national attention after many in the media misinterpreted its findings.
The study, titled “A Silver Lining, the Connection Between Gas Prices and Obesity,” found that an additional one-dollar in real gas prices could reduce obesity in the U.S. after five years.
Courtemanche found that when gasoline prices go up, people tend to drive their cars less and seek other forms of transportation, increasing the amount of exercise they get from walking. Courtemanche also found that with higher prices, people eat at restaurants less frequently and thereby consume fewer calories.
However, the paper received skepticism.
A number of writers and national talk show hosts, including Rush Limbaugh and Jay Leno, felt that Courtemanche had implied that the government should increase gasoline prices as a way of reducing the country’s obesity.
In the September 13 edition of NBC’s “The Tonight Show,” Leno mentioned the study in his monologue, and Limbaugh discussed the study on his Web site.
Courtemanche denied the allegations, saying that many people had misinterpreted his findings. He explained that the study only found that increasing gasoline prices could reduce obesity but that the study did not advocate such a price increase or suggest that gasoline taxes would benefit social welfare.
“My paper makes no effort at all to determine whether gasoline taxes would be beneficial for society,” said Courtemanche.
Courtemanche also concluded that about 13 percent of the total rise in obesity from 1979 to 2004 could be attributed to falling real gas prices during the period, with the other 87 percent of the total increase in obesity arising from other factors.
While actual gasoline prices have risen between 1979 and 2004, the study focused on real gasoline prices, which is the price of gasoline when adjusted for inflation over the period. When adjusted for inflation, the real price of gasoline actually fell over that period.
In his study, Courtemanche compared average real state fuel prices with trends in obesity over two decades, 1984 to 2004, while also isolating potential confounding factors such as marital status, income, race and education.
He suggested that future research could focus on the potential social benefit of increases in fuel prices, but he warned that such studies would need to account for all other potential consequences of increased fuel costs.
“If you’re talking about obesity, you don’t want to enact a policy that would make people poorer, because if people become poorer, then they tend to gain weight,” added Courtemanche. “If you did do something like raise the gasoline tax then you’d want to mash that with some subsidy or reduction in some other tax, like reducing the payroll tax, so that in the end people aren’t left any poorer.”
Additionally, a Sept. 11 article in Reuters about Courtemanche’s study mistakenly printed that he found that the fall in real gas prices from 1979 to 2004 completely explained the rise in obesity in the country.
The misprint led some writers to misread the study’s findings, including CNBC columnist Jane Wells, who criticized the study in a Sept. 12 blog post.
The Reuters story was eventually corrected to reflect the fact that the fall in real gasoline prices explained only 13 percent of the rise in obesity from 1979-2004, and Wells posted an apology on her blog on Sept. 18.
Courtemanche said that he enjoys the publicity, though he admitted he was upset about the misinterpretations of the media.
“I don’t mind skepticism about my results,” he said. “The thing that is more bothersome is when people take it out of context and misinterpret it.”Print This Post