Updated

Most children and teens who are overweight think that they are actually the right weight, a new report from the Centers for Disease Control and Prevention finds.

For the report, researchers asked U.S. children ages 8 to 15 whether they considered themselves to be "fat or overweight, too thin, or about the right weight."

Overall, about 30 percent of the children had misperceptions about their weight: For instance, they were normal weight, but thought they were overweight or too thin; or they were overweight or obese but thought they were underweight or about the right weight. [10 Ways to Promote Kids' Healthy Eating Habits]

But among the overweight children, most had misperceptions about their weight. The researchers found that 81 percent of overweight boys and 71 percent of overweight girls thought they were about the right weight. In addition, about half of obese boys and a third of obese girls thought they were the right weight.

On the other hand, most normal-weight children (87 percent) considered themselves to be the right weight, while about half of underweight children considered themselves to be the right weight (the other half considered themselves to be too thin).

A higher percentage of children from low-income families had misperceptions about their weight, compared with the children of high- and middle-income families, according to the report.

"Accurate self-perception of weight status has been linked to appropriate weight control behaviors in youth," the researchers, from the CDC's National Center for Health Statistics, wrote in the report published today (July 23). The new findings may help inform public health interventions, they said.

Previous studies have shown that parents also misperceive their children's weight, and healthcare providers misperceive their patient's weight, said Dr. Ihuoma U. Eneli, medical director at the Center for Healthy Weight and Nutrition at Nationwide Children's Hospital, who was not involved in the study. "It's not just the kids," that have misperceptions about weight, Eneli said.

One reason for the misperception may be inadequate knowledge about what a healthy weight looks like, Eneli said. "As the prevalence of obesity has increased over time, our perception of what is a normal weight has also changed," Eneli told Live Science. "If people look heavier, then heavier starts looking like the norm."

Having a correct perception about weight status may be more important for teens than for younger children, Eneli said. For teens, it helps if both parent and child have the same perception of the child's weight, because then it's easier for the family to make healthy changes together, Eneli said.

But Eneli said she does not usually discuss weight with young children instead, she emphasizes the lifestyle changes that a child should make to be healthier.

"I dont emphasize weight when the child is a preteen, thats a discussion I would rather have with the parent," Eneli said.

Some studies have shown that how a parent perceives a child's weight drives how they feed their child, more so than the child's actual weight, Eneli said.

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