Overweight children appear to be especially susceptible to the lure of fast food, a study found. They stuff themselves even more ravenously than other youngsters do and are less able to compensate by eating sparingly the rest of the day.
The study is nutrition experts’ latest attempt to nail down the link they suspect exists between fast food and the daunting increase in obesity, which now afflicts one in 10 children and teenagers in the United States.
Even though the drive-through window is often blamed for Americans’ big and growing weight problem, its exact role is less clear, since people overindulge in many ways while getting little exercise. Certainly the meals can be huge and calorie dense. But many indulge in the occasional triple cheeseburger with bacon without bulking up.
“Everybody is eating fast food, in all socio-economic groups,” notes Dr. David Ludwig, a child obesity expert. “But if everybody is eating it, why are some people still thin?”
His team at Boston’s Children’s Hospital set out to find the answer by setting up an experiment at a food court. The volunteer eaters were 26 obese children and 28 who were of normal size.
“Eat as much or as little as you like, until you have had enough,” the youngsters were told. “There is more food available, and you may eat as much as you want.”
Everyone started out with the equivalent of a supersize value meal of chicken nuggets, fries, cola and cookies that added up to 2,100 calories. And eat they did. Large or lean, the children wolfed down plenty of food.
“They consume more than half of the calories they need for the whole day in about 20 minutes,” Ludwig said.
But in the end, the big kids ate more. The obese youngsters downed 67 percent of their daily calories in one sitting, while the normal-size ones got 57 percent.
Next, the researchers made an unannounced call to see how much the same youngsters eat over a whole day when on their own. On a day they had fast food, the obese youngsters ate a total of 400 more calories than on a day when they ate at home. However, the lean kids ate the same amount of total calories whether they had a fast food meal or not.
They concluded that overweight children are more susceptible to gargantuan fast food meals because they do not have — or have somehow lost — the ability to even out their intake by cutting back over the rest of the day.
“Do certain people have trouble compensating for energy-dense fast food? This study suggests overweight people may,” said Simone French, a psychologist at the University of Minnesota.
The research was presented at the annual meeting of the North American Association for the Study of Obesity, which concluded Wednesday. Among other reports at the meeting:
—Researchers from Johns Hopkins University have been following 1,337 men since their graduation from medical school between 1948 and 1964. They found that the average weight gain was one-third of a pound per year up to age 65. After that, weight plateaus, and losing weight in later years is not healthy or normal.
—To test the theory that people eat less if they take smaller bites, researchers from the Pennington Biomedical Research Center in Baton Rouge, La., fitted overweight volunteers with a “behavior modification tool” that “fits into the upper palate of the mouth and reduces the size of the oral cavity.” In the two-day experiment, the gadget cut their daily intake by 659 calories. A longer study will be necessary to prove it works over time to reduce weight.
—Russ Lopez of Boston University looked for a link between urban sprawl and obesity. He rated sprawl in U.S. metropolitan areas on a 100-point scale and matched it with the amount of physical activity people reported in a nationwide survey. For each one-point increase in sprawl, people’s physical activity declined by one-third of 1 percent.