COLUMBIA -- Every science experiment starts with a question.
In Steven Blair's case, that question is an urgent one: Is the obesity epidemic plaguing the nation, and South Carolina, in particular, driven more by overeating or by inactivity?
Blair, a professor in the University of South Carolina's Department of Exercise Science and Epidemiology/Biostatistics, will spend the next year sorting through the question.
First, though, he needs the help of 400 overweight but relatively healthy men and women, between the ages of 21 to 35, to take part in a study about what is behind obesity.
In South Carolina, participants shouldn't be hard to find. Recent reports by the Trust for America's Health and the Robert Wood Johnson Foundation showed what any casual observer at the S.C. State Fair, readily can see: Many South Carolinians -- two-thirds of the population -- are overweight; about 31 percent are obese.
Even the state's top beauty queen, Miss S.C. Bree Boyce, used to be overweight. But that was 110 pounds and one glittering tiara ago.
Blair's experiment aims to find out, specifically, why people pack on the pounds. That knowledge then could be used to help shrink waistlines.
Blair has a theory of his own.
Rather than the notion that Americans are getting fatter because they slurp down supersized, sugary drinks and chow on cholesterol-laden fast food served up in gigantic portions, Blair thinks inactivity is the bigger culprit.
He points to changes in the way that Americans work, cook and even clean their homes as evidence that what used to take some get up and go now is done with the flip of a switch.
Gone, he noted, are the days when large numbers of Americans earned their living by working on the farm.
Microwave ovens heat up meals that used to take time and energy to prepare. Many lawnmowers and even vacuum cleaners are self-propelled.
To get the same amount of work done as before, Americans today have to work less. "This shift in energy expenditure is the reason for the obesity epidemic, in my opinion," Blair said.
Blair is a proponent of the idea that a person can be "fat but fit," and he has disdain for what he calls the "obesity mafia," which he says has trained Americans to think that any excess weight is dangerous.
That argument is pounded home, over and over, in magazine covers featuring thin celebrities and, frequently, diet tips so you, too, can look like your favorite star. The view of how much weight is too much has gotten so out of whack, Blair argues, that former President George W. Bush, an avid runner and cyclist, is considered overweight by some.
"Lazy. Harder to get a job. Harder to get a girlfriend," Blair said. "We assign all sorts of bad motives to overweight people. ... We worship thinness. Most of us will never look like those movie stars no matter what we do."
While Blair isn't alone in thinking one can be "fat but fit," other scientists don't share that view.
Runners World magazine recently featured an article with dueling opinions on the "fat but fit" theory. Glenn Gaesser, of the Healthy Lifestyles Research Center at Arizona State University, said you can be fit and fat. But another scientist, Dr. Amy Weinstein of Harvard Medical School, who specializes in the health impacts of obesity, wasn't buying it.
"Physical activity cannot completely reverse the ill effects of carrying excess weight on diabetes and cardiovascular disease," Weinstein is quoted as saying.
Blair said there are no convincing data that diet is the main driver of the country's obesity problem. He said he hopes his study, where the caloric intake, physical activity and health of participants will be monitored and charted for a year, can shed some light on the debate.