Sweet sodas, candy and other kinds of junk food are not making Americans fat, say U.S. researchers who report they've found no correlation in 95 percent of the population between junk food consumption and a measure of body fat.
Analyzing national data from 2007 and 2008 showed that people on average consumed nearly identical amounts of junk food whether they were at healthy weights or obese, the researchers at Cornell University say.
There is no correlation between the consumption of junk food and body mass index or BMI, a common measure of body fat, they report.
This is despite long-held assumptions that chowing down on junk food and indulging in sweetened drinks were significant factors in the increasing trend toward obesity among Americans.
"These are foods that are clearly bad for you, and if you eat too much of them, they will make you fat, but it doesn't appear to be the main driver that is making people overweight and obese," says lead researcher David Just, co-director of the university's Center for Behavioral Economics in Ithaca, N.Y.
The researchers, while acknowledging that junk food is an unhealthy dietary choice, say junk food is getting far more blame for America's obesity epidemic that it deserves.
"Simply put, just because those things can lead you to get fat doesn't mean that's what is making us fat," Just says.
Targeting junk foods, he suggests, is ineffective and possible self-defeating if it distracts from the true underlying causes of obesity: lack of exercise or physical activity and insufficient consumption of healthier foods like fruits and vegetables.
Those causes likely have much more influence on a person's weight than just junk food consumption, Just says. Diet choices and exercise are the best ways to lose weight, he says.
"There is nothing flashy about that advice," he says. "It's not magic; there is no silver bullet here."
Health policies that are directed solely at the issue of junk foods and sweet drinks could squander resources better directed at more effective community health decisions, he suggests.
"If you want to try and prevent obesity, or want to create policy that is going to help people, simply addressing the availability of junk foods and sodas isn't going to do it," says Just. "This isn't the difference between fat people and skinny people. It's other things."
The study has been published in the journal Obesity Science & Practice.