Low intelligence causes obesity? What research shows

man, hamburger, fries, istockphoto, 4x3
man, hamburger, fries, istockphoto, 4x3

(CBS) Does being not-so-smart make people not-so-skinny? Experts say a controversial new study adds to a growing body of evidence linking low intelligence to weight problems. It shows that men who score low on IQ tests in adolescence are more likely to be overweight in middle age.

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For the study - described at a recent meeting of the American Heart Association - researchers in Sweden compared the waist-hip ratios of more than 5,000 40-year-old men to their scores on IQ tests taken when they were around 18 years of age. The researchers found a strong inverse relationship between the ratios, which scientists use to gauge obesity and heart disease risk.

In other words, the fattest men had the lowest IQ scores.

What might explain the link between low intelligence and middle-aged spread? One possibility is that less-intelligent people make poorer food choices, Dr. Robert H. Eckel, professor of medicine at the University of Colorado School Medicine, told CBS News. Another, he said, is that they are more averse to exercising than people who are more intelligent.

But Dr. Eckel, a past-president of the association, stressed that those are simply possible explanations, saying "The study raises more questions than it answers."

But the study's author, Uppsala University's Dr. Jerzy Leppert, was less guarded in his assessment of what might explain the link between low IQ and obesity. In an email to CBS News, he said men with limited "intelligence resources" might find it hard "to absorb all the messages that reach them. Their parents usually have the same problem with low IQ, which further limits their ability to adopt more healthy way of life."

Dr. Leppert said it was time for the limited resources available for obesity prevention to be aimed squarely at people of limited intelligence, acknowledging that "our findings are not convenient for policy makers."

What do you think? Does the study point out an inconvenient truth? Or is it unfair to fat people?