March 17, 2004 -- "Do it now," Americans like to say. But we're more likely to be talking about eating a pizza than working out.
And that's why we're so fat, argue economist John Komlos, PhD, of the University of Munich, Germany, and colleagues. In a provocative paper, the researchers find that Americans started getting fat about the same time they stopped planning for the future.
Their major evidence: As Americans began spending more and saving less of their income, their weight began to rise. The less we save for the future, the more weight we gain. People living in countries that that save more of their income are less obese. The findings appear in the current issue of the Journal of Biosocial Science.
"People have tried to look at a lot of reasons why Americans are getting so overweight. But nobody has thought about the idea of connecting it to impatience," Komlos tells WebMD. "If you are willing to forgo present satisfaction for future benefits, you are patient. If, however, you want your satisfaction right now, then you are going to have that extra dessert and that extra ice cream and you are not going to be able to forgo the pleasures of today."
Obesity: The Future Is Now
The future, said French novelist Gustave Flaubert, is the worst thing about the present. Americans solve this dilemma by simply ignoring the future. Economists would say Americans have a "high rate of time preference." In plain language, this means we ignore future health risks and maximize current consumption.
Such people are impatient, says study co-author Barry Bogin, PhD, an anthropologist at the University of Michigan-Dearborn.
"When it comes to spending money, they say, 'Let's go out and buy the stuff I want.' When it comes to food, they say, 'If they put it all in front of me now, I will eat it,'" Bogin tells WebMD.
By now, everybody knows that if you eat less and exercise more, you'll lose weight. Keep it up, and you will be more healthy. But that means valuing the future so much that you'll shove your plate aside and make time to go jogging or to work out at a gym. Fewer and fewer Americans do this.
"All you have to do is get out and exercise for an hour, but people won't do that because of their time preference," Bogin says. "They say, 'Why invest an hour? I should be writing another paper, doing more work, watching this thing on TV -- whatever seems important right now."
A widespread phenomenon such as obesity has no single cause, notes study co-author Patricia K. Smith, PhD, an economist at the University of Michigan-Dearborn.
"People have to think about how what they do now affects the future -- about what [they] will do about the future," Smith says.
And that's getting harder and harder for more and more of us. Even something as seemingly innocuous as watching television becomes part of the problem.
"We know that when people watch TV, they eat junk food more than if they were reading or listening to music," Bogin says. "It gets complex here. Does TV cause obesity? No. But a combination of poverty, low education, watching TV, the hopelessness of being poor in a rich nation, it all adds together and raises your time preference, and you say, 'Who cares about the future? I'm going to eat the whole pizza right now.'"
Impatience, Obesity, and Science
Komlos, Smith, and Bogin are quick to say that their impatience hypothesis is by no means a proven fact. But it does fit the little data that exists -- and it makes sense.
What would a serious health scientist say? Michael J. Kuhar, PhD, heads the division of neuroscience at Yerkes National Primate Research Center at Emory University in Atlanta. Part of his research has focused on the brain chemistry of obesity.
"It may be that when you really look into this further, the theory may need some modification. It may not exactly apply in the way it now seems to do -- or this time preference may apply only in some cases," Kuhar tells WebMD. "My feeling is this is way out but should not be dismissed. Things like this are interesting and possibly beneficial. I am not ready to accept this as gospel yet, but it is very, very interesting."
The Past and Present of Future Fear
America's impatience didn't pop up overnight. And it won't disappear quickly, Komlos warns.
"It is not only just now happening. It is a cumulative process that has been going on for several decades," he says. "And the obesity rate has been increasing over decades. This is not an immediate once-and-for-all pattern but something that has been creeping up on us. Then all the advertisements, all the media, are pushing us to satisfy our urges now and not to wait. All the pressures on us are for buying the car now, getting fast food now."
We pass these attitudes on to our children, he says. And by the time they've reached their late teens, their preference for time present over time future may be hard or impossible to reverse.
"Once you learn these behavioral characteristics -- once your time preference is set in childhood and adolescence -- it probably isn't going to change in your lifetime," Komlos says. "It is a kind of parameter that stays with you."
Then what can be done? Komlos and Bogin urge a concerted public health effort.
"We really have to do what we did with cigarettes: Wage a relentless campaign to get rid of everything that induces people to eat bad stuff," Bogin says. "We got rid of Joe Camel. Now we have to get rid of inappropriate children's food advertising."