Those efforts to fight obesity in schools? Think younger. A new study finds that much of a child’s “weight fate” is set by age 5, and that nearly half of kids who became obese by eighth grade were already overweight when they started kindergarten.
The prevalence of weight problems has long been known – about a third of U.S. kids are overweight or obese. But surprisingly little is known about which kids will develop obesity, and at what age.
Researchers think there may be a window of opportunity to prevent it, and “we keep pushing our critical window earlier and earlier on,” said Solveig Cunningham, a scientist at Emory University. “A lot of the risk of obesity seems to be set, to some extent, really early in life.”
She led the new study, which was published in the New England Journal of Medicine and paid for by the federal government.
It tracked a nationwide sample of more than 7,700 children through grade school. When they started kindergarten, 12 percent were obese and 15 percent were overweight. By eighth grade, 21 percent were obese and 17 percent were overweight.
Besides how common obesity was at various ages, researchers focused on the 6,807 children who were not obese when the study started, at kindergarten entry.
Nearly half of kids who started kindergarten overweight became obese teens. Overweight 5-year-olds were four times as likely as normal-weight children to become obese (32 percent vs. 8 percent).
By eighth grade, 17 percent of black children had become obese, compared with 14 percent of Hispanics and 10 percent of whites and children of other races.
The study’s findings do not mean that it’s too late for schools to act, but their best tactic may be to focus on kids who are overweight and try to encourage exercise and healthy eating, Cunningham said.
The work also shows the need for parents, doctors, preschools and even day care centers to be involved, said Stephen Daniels, a University of Colorado pediatrician and a spokesman for the American Heart Association.
“You can change your fate by things that you do early in life,” with more exercise and eating a healthy diet, he said. “Once it occurs, obesity is really hard to treat. So the idea is we should really work hard to prevent it.”