Gable said there are likely other factors at play. For example, obese children may miss more school days, which would affect their performance. Obese children also are more likely to have sleep apnea, which, if untreated, can affect daytime performance.
The bottom line, Gable said, is that "parents need to protect children from obesity as long as they possibly can. Establish a healthy lifestyle that prevents this from happening. Once someone is obese, it's really hard to change."
If your child already is overweight, Gable said, it is important to get them on a course to better habits. But, she added, it is also important to "help children learn that this is not who they are." Their weight doesn't define them.
It is also crucial that any changes to diet and exercise routine affect the whole family.
"The whole family's routines have to change. Not just one person's plate or one person's activity level," Gable said.
For her part, Copperman said, "It's never too late to start helping your child live a healthy lifestyle."
"It's kind of like driving a car on the expressway," she said. "You can't suddenly put the car in reverse. If your child is already overweight, you need to step on the brakes to stop the weight gain."
The U.S. Centers for Disease Control and Prevention offers advice on maintaining a healthy weight in children.
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