Twice as many kids in the U.S. are overweight today as two decades ago, but a panel of experts says it is not clear how doctors can help.

In a newly released report, the U.S. Preventive Services Task Force concludes that there is little proof that the current practice of screening children in the doctor’s office for overweight and obesity prevents obesity-related illness.

“The evidence is insufficient to recommend for or against routine screening … in children and adolescents as a means to prevent adverse health outcomes,” the panel noted.

The task force also concluded that behavioral counseling and other interventions delivered by doctors during routine office visits may not do much good either.

“There are several gaps in the research evidence on screening and interventions for overweight children and adolescents in the primary care setting,” they wrote.

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Value of BMI Mixed

The panel based its report on a review of studies evaluating the impact of obesity screening and early treatment of overweight in kids and teens in the clinical setting.

The studies indicate that body mass index (BMI) -- an indirect measure of body fat which uses a person's weight -- may not be a useful measure in younger children.

In children, BMI is age and sex specific; when a child's BMI measure is greater than 95 percent of his peers, the child is categorized as overweight or obese. Children that are overweight and obese have a higher risk of being overweight and obese adolescents.

Health-related illness associated with childhood and adolescent obesity has the potential to persist into adulthood.

But Evelyn Whitlock, MD, MPH, who led the review team, says the value of measuring overweight in young children as a predictor of obesity in adulthood is unknown.

“The issue is what do you do with a 3-year-old in the 95th percentile, and what do you tell his parents,” she tells WebMD. “We don’t have the answers.”

She adds that programs addressing overweight in older children and teens are not widely available, and that there is little evidence that intervention efforts aimed at this age group are effective.

The review is published in the July issue of the American Academy of Pediatricians’ journal Pediatrics.

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Parents Often Don’t See Problem

In a related study also published in the journal, researchers reported that parents frequently don’t recognize that their child is overweight, or say they feel powerless to do anything about it.

The researchers surveyed 151 parents of children; 62 percent of the kids were overweight or obese. The researchers found almost half of the parents 44 percent did not see their child’s weight as a problem and were classified as having no interest in changing behaviors in the next six months. Another 17 percent of parents did recognize that their child had a problem, and were thinking about making a change, but not soon.

Pediatrician and study co-author Cynthia DeLago, MD, MPH, tells WebMD that parents who were overweight themselves often recognized the problem in their children, but had taken no action.

“We don’t know exactly, but it is likely that many of these parents just felt defeated by their own struggles with weight,” she says. “You might hear, ‘Everybody in our family is big. It’s genetics, and there isn’t anything we can do about it.’”

The researchers found that parents of children who were 8 years old or older were more likely to be ready to address their child’s weight issues than parents of younger children.

DeLago says the realization that parents’ attitudes about their children’s weight vary widely has changed the way she practices medicine.

“It is important to understand where a parent is coming by asking if their child’s weight is a concern,” she says. “The discussion that you have with a parent who says ‘yes’ is very different from the one you have with one who says ‘no.’”

She adds that parents are often reluctant to take action until the child sees his or her weight as an issue, usually around the time they hit middle school.

“The problem is that by then you have established certain eating patterns that are really hard to break,” she says.

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So What Can a Parent Do?

While she agrees that studies addressing childhood obesity are badly needed, pediatric weight loss specialist Melinda Sothern, PhD, says there are effective intervention programs for overweight kids.

Sothern directs the Childhood Obesity Prevention Laboratory at Louisiana State University, and is co-author of the book Trim Kids.

“A good program won’t focus on weight,” she says. “It will focus on healthy eating, increasing physical activity, and decreasing the time a kid spends in front of the television or computer.”

Interventions aimed at younger children should focus on the home environment, she says. Some of the most important changes include:

Limiting screen time -- TV, computers, and video games -- to less than 2 hours a day. Making sure kids have plenty of opportunity for exercise, especially unstructured play. Having regular sit-down family meals, and banning snacking in front of the television. Getting junk foods out of the house, and replacing them with fruits, vegetables, and other healthy foods.

“The key is for parents to take control of the home,” she says. “Young children, especially, will eat what is available. That means junk food if it is there and healthier fare if it isn’t.”

Parents are less able to influence their older children’s behaviors with regard to weight, food choices, and activity, and they should not even try unless asked, Sothern says.

“Parents shouldn’t get into struggles about weight and food with teenagers because there are so many other things going on,” she says. “We don’t really know what works with teens, but we do know that the worst thing a parent can do is confront their teenaged child about their weight.”

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By Salynn Boyles, reviewed by Brunilda Nazario, MD

SOURCES: Whitlock, E. Pediatrics, July 2005; vol 116: pp 94-101, 125-143 and 205-209. Evelyn Whitlock, MD, MPH, Center for Health Research, Kaiser Permanente, Portland, Ore. Cynthia W. DeLago, MD, MPH, St. Christopher’s Hospital for Children, Philadelphia. Melinda Sothern, PhD, director, Childhood Obesity Prevention Laboratory, Louisiana State University Health Sciences Center, School of Public Health.