By Robert Preidt
The findings support the theory that obese children have a heightened reward response to food, and that their brains could be wired in a way that makes them crave higher amounts of sugar, the researchers said.
"The take-home message is that obese children, compared to healthy-weight children, have enhanced responses in their brain to sugar," first author Kerri Boutelle, a professor in the psychiatry department at the University of California, San Diego, said in a university news release.
"That we can detect these brain differences in children as young as 8 years old is the most remarkable and clinically significant part of the study," added Boutelle, founder of the university's Center for Health Eating and Activity Research.
For the study -- published online Dec. 11 in the International Journal of Obesity -- the researchers scanned the brains of 23 children, ages 8 to 12, as they tasted sugar water.
Compared to healthy-weight children, obese youngsters had greater activity in areas of the brain involved in perception, emotion, awareness, taste, motivation and reward, the study found.
"Any obesity expert will tell you that losing weight is hard and that the battle has to be won on the prevention side, Boutelle said. "The study is a wake-up call that prevention has to start very early because some children may be born with a hypersensitivity to food rewards or they may be able to learn a relationship between food and feeling better faster than other children."
About one-third of American children are overweight or obese. Research shows that 80 to 90 percent of obese children become obese adults.