Both energy and obesity have become growing socioeconomic concerns in the United States, and although the problems seem independent, they share a link.

A recent Engineering department study claims that the U.S. has consumed as much as 1 billion gallons or more of fuel each year due to excess weight in the population. This study implies that obesity is increasing fuel consumption.

The study was conducted by Sheldon Jacobson, professor of computer science, and Douglas King, doctoral student in Engineering. It was a follow-up to a 2005-2006 study that Jacobson did with Laura McLay, a former doctoral student, on the economic impact of obesity on automobile fuel consumption.

During the time period between the two studies there was an increase of about 200 million gallons of fuel used due to the increasing weight of Americans, Jacobson said.

The data compares the weights of Americans since 1960 and how many additional gallons of fuel was needed to compensate for the extra weight. Jacobson said adult Americans are an inch taller on average and 25-30 lbs. heavier today than in the 1960s.

Jacobson said that the study indicates that energy and obesity are inextricably linked.

“If we simply make a concerted effort to reduce our energy consumption we may discover that our obesity problem will be lessened,” Jacobson said. “We have an energy problem in this country and we have an obesity problem, and if we try and address the former without considering the latter, we’re basically dooming ourselves to failure. We have to consider them together.”

David Buchner, professor of kinesiology and community health, said obesity refers to having a body mass index of 30 or higher.

Body mass index is calculated using a person’s height and weight, and is accepted as an accurate measure of body fat. Buchner said the obesity epidemic in the U.S. started in the 1980s and obesity rates have steadily increased since then.

Consequently, Buchner said there are ways to combat both the obesity and fuel consumption problems.

“If you promoted active transportation, then not only are they (people) not using cars which results in less fuel consumption … they would be less likely to be overweight,” he said.

Buchner said some forms of active transportation include walking or biking to a destination.

Fred Giertz, head of the economics department, said that overweight Americans are not the primary reason for the enormous U.S. consumption of fuel, but rather being a rich country and a country with a disperse population contributes.

“How fat people are has some impact, but it’s probably pretty small related to the more primary kinds of issues,” Giertz said. “There may be some relationship between how rich we are and how fat we are. The two may not be independent, so it’s hard to isolate it as a separate cause.”

Similarly, King said the fuel consumption data of overweight or obese people comprises only about 1% of the total American fuel consumption.

“Our goal was to quantify what the direct relationship is between obesity and fuel consumption,” he said.

Jacobson said he and King are continuing to study obesity and its effects on the fuel economy and are currently investigating whether fuel consumption contributes to obesity.