(HealthDay)—Although you might think being a member of the "clean plate club" is something that stops when a child is young, new research suggests that up to two-thirds of parents still encourage teenagers to finish all the food on their plates, even if the teen is overweight.
The study found that the use of controlling food behaviors was common in parents of adolescents, with some parents pressuring their kids to eat more and others pressuring their kids to eat less.
Not surprisingly, restrictive behaviors were more common in parents of children who were overweight or obese, while pressure-to-eat behaviors were more common in children who weren't overweight.
"Parents do use high levels of control, such as restriction and pressure to eat," said study author Katie Loth, a registered dietician, doctoral candidate and research assistant at the University of Minnesota in Minneapolis.
"I was surprised at some of the parent behaviors, like feeling that their children should clean their plates and not waste food," Loth said. "In the 1950s, cleaning your plate meant something different. Portion sizes have gotten bigger over time, and if you encourage kids to rely on environmental indicators, like how much food is on their plates or the time of day, they'll lose the ability to rely on internal cues to know whether they're hungry or full."
Results of the study were released online April 22 and will be published in the May print issue of the journal Pediatrics.
As obesity rates among America's adolescents have been rising, researchers have been looking for factors that might be modifiable to help keep teens at a healthy weight. Parental food-related behaviors, whether it's restricting food or encouraging children to eat more, have long been considered a factor in children's weights.
Loth and her colleagues wanted to look at a diverse group of parents and teens to see if parental food behaviors were, in fact, linked to weight status in teens.
Data for the study came from two population-based studies that included parents and teens. One study was conducted in 2010, and the other was done in 2009 to 2010. A total of more than 2,200 teens with an average age of 14.4 were included in the studies, as well as nearly 3,500 parents.
Examples of restrictive behaviors were positive responses to statements such as, "I have to be sure that my child does not eat too many sweets," or "If I did not guide or regulate my child's eating, he or she would eat too much of his or her favorite food."
Examples of pressure-to-eat behaviors were positive responses to statements such as, "My child should always eat all of the food on his or her plate," or, "If my child says, 'I am not hungry,' I try to get him or her to eat anyway."
The researchers found that restrictive food behaviors were more common in parents who had overweight or obese children. Pressure-to-eat behaviors were more common in parents of children who were normal weight.
One expert noted that what is a normal weight has been skewed in recent years.
"There's now so much obesity in the United States that when we see a child who is normal weight, inevitably, a parent will think the child is too skinny," said Dr. Michael Hobaugh, chief of the medical staff at LaRabida Children's Hospital in Chicago. "But if a pediatrician charts that child's height and weight, he or she may even be overweight. There's a wide range of normal, and for many teens it's normal to be slender and gangly. Children aren't supposed to be shaped like linebackers."
The study also found that fathers were more likely to use pressure-to-eat behaviors, and adolescent boys were more likely to be pressured to eat by their parents than were adolescent girls.
Both Loth and Hobaugh said a better way is for parents to model healthy eating behaviors.
"Children will eat like you do. You have to model portion control and good food choices," Hobaugh said. "The whole family needs to make a decision together to increase the amount of fruits and veggies, and to reduce empty calories from drinks."
"Parents need to allow their children to have freedom when eating," Loth added. "Parents can control the types of foods that are on the table, and you can bring lots of healthy food to the table. Then let your child choose how much they want to eat. Let them regulate their own intake."
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Learn more about helping your child maintain a healthy weight from the U.S. Centers for Disease Control and Prevention.