Obesity is more and more common in children, even very young children. Many parents would like to limit what their children eat, but you may have noticed—telling kids what to do doesn't always work. Researchers at the University of Pennsylvania looked at the relationship between children's obesity and parents' attitudes about feeding their kids.

What the researchers wanted to know: How do parents' attitudes and children's genetic risk for obesity work together to influence the child's weight?

What they did: The researchers used 57 white families who are enrolled in a long-term study at the Children's Hospital of Philadelphia. Some of the children had overweight mothers, which means the kids were at high risk for obesity, and some had lean mothers. Researchers weighed the children and calculated each child's body mass index. They also gave parents questionnaires that asked how they felt about their child and about their feeding style: how much they tried to restrict their child's eating, how much they pressured their child to eat more, and how much they monitored the child's fat intake.

What they found: Maybe the most interesting finding is that among high-risk kids, those whose parents restricted food at age 5 were likely to have a higher body mass index at age 7. So stopping them from eating more at meals actually made them fatter, probably by preventing them from learning to eat until they felt full and then stopping. The researchers also learned a lot about feeding attitudes, for example that they don't change much over time‑parents who were worried about their kids' weight at age 5 were likely to still be worried at age 7.

What the study means to you: Experts already know that restricting children's eating doesn't help—recommendations usually tell parents to encourage their kids to eat more fruits and vegetables. Also, since the study found a difference between children with overweight and lean mothers, those children might need different weight-control plans.

Caveats: It's a small study, and everybody's white. These results wouldn't necessarily apply to people who aren't white. Also, they didn't actually measure what children were eating.

Find out more: The American Academy of Family Physicians has a website on kids' health, including a quiz game called "Mission Nutrition".

Read the article: Faith, M.S., et al. "Parental Feeding Attitudes and Styles and Child Body Mass Index: Prospective Analysis of a Gene-Environment Interaction." Pediatrics. October 2004, Vol. 114, No. 4, pp. e429-e436.

Abstract online: http://pediatrics.aappublications.org