In 69 studies of more than 15,000 children, researchers found many parents with an overweight child thought their son or daughter was at a healthy weight or below. Others with an obese kid thought the child was normal or just a bit heavy.
"We know that parents play a very crucial role in preventing childhood obesity, and interventions are most successful if they involve parents," said Alyssa Lundahl. She led the study at the University of Nebraska-Lincoln.
But, Lundahl said, if parents don't recognize their child is overweight or aren't concerned, they aren't going to take steps to address it.
"Previous research has found that when parents' perceptions are corrected, they do start to take action and encourage their children to become more active and maybe turn off the TV and go outside and play," she told Reuters Health.
The studies included children and teenagers ages two and up. In each case, researchers had parents assess their child's size using pictures, rating scales or other techniques. Then they measured the children to determine whether they hit weight-to-height cutoffs for being overweight or obese.
Just over half of parents - 51 percent - thought their overweight child was normal or underweight or thought their obese child was normal, underweight or just overweight.
Image: Overweight child, via Shutterstock