Junkfood Science: Parents know best when it comes to their kids — The experts weigh in to convince us otherwise

December 20, 2007

Parents know best when it comes to their kids — The experts weigh in to convince us otherwise

Do parents really need a reality check? Are they actually in denial and blind to their children’s obesity? And do most parents truly not care about the health of their children and fail to take responsibility to help them? While those were the message points we heard in the news and medical literature last week, let’s go directly to the source for the facts. What it reveals is a much bigger story.

Researchers at the Communicable Diseases and the University of Michigan Child Health Evaluation and Research (CHEAR) Unit, led by Matthew M. Davis, M.D., M.A.P.P., published the results of a poll conducted for C.S. Mott Children's Hospital. Yes, this was a report of a consumer poll conducted by Knowledge Networks, Inc., a market research company. It conducted an online survey of a contracted group of people they call their KnowledgePanelSM. According to the company, the panel is representative of the U.S. population and its statistical projections can accurately estimate incidences, trends and market sizes, and provide figures for marketing purposes.

As we know, poll questions can be worded and ordered, and the answers interpreted so as to create any finding a poll sponsor wishes. Whether this marketing technique can be objective medical research was examined previously. We’ll look at what this poll reported and then how the findings were spun.


In the opening paragraph of their report, Dr. Davis and colleagues laid out the premises, or working assumptions, for their poll, saying:

It is critical to address obesity in the childhood years — at home, and in schools and in other community settings. But in order to address childhood obesity, parents must recognize that children have excess weight for their height. Parents must also be concerned enough to want to do something about their children's obesity.

They provided no medical evidence for a critical need to address childhood obesity. In fact, children today are not sicker or expected to live shorter lives than their parents. According to the latest Health United States 2007 report, children born today are healthier and expected to live longer than at any other time in our history. Babies born in 2004 can expect to live 75.2 years if male and 80.4 if female. Compared to babies born in 1990, boys today are expected to live 3.4 years longer and girls 1.6 years longer.

And the promotion of weight-height measures for individual children as a way to identify those in need of interventions is similarly without support. According to scientists at the CDC’s National Center for Health Statistics, BMI is a screening tool [for public surveillance], not a diagnostic tool, and BMIs over cut-offs don’t equate to clinical complications or health risks. After a comprehensive review of 40 years of evidence — about 6,900 studies and abstracts — on screening and interventions for childhood and adolescent “overweight,” the U.S. Preventive Services Task Force recently found no quality evidence to support that childhood “overweight” is related to health outcomes.

The conduct of the poll

This past summer, in conducting the poll for CHEAR, Knowledge Networks had surveyed 2,060 adults. About two-thirds of them were parents. The parents were asked the height and weight of their oldest child, which the researchers used to calculate the children’s BMI and rank them as “healthy, overweight, or obese based on age- and gender-specific ranges.”

Note: Already, the use of these terms alerts us to a bias, as these are not used by the CDC or medical experts, but by those trying to convince us of an epidemic of “childhood obesity.” In addition to the problems with using body mass indexes and the new BMI-growth charts for growing children, the term “obese” has not been used. American children weighing above the 95th percentile are termed “overweight,” and those in the 85th-95th percentile are termed “at risk for overweight.” To create perceptions of an epidemic, some have begun to combine both, using new labels of “obese” and “overweight,” to effectively double the numbers of children considered overweight.

Increases in the incidences of childhood “obesity” and “overweight” are based on the numbers crossing those arbitrary thresholds for height and weight — they are not the increases in the actual weights and heights of kids.

“The figure of 30% often reported in the media is an overstatement that ought to be qualified every time it is used, since about two-thirds of those are mislabelled as overweight. They are simply bigger and possibly fatter than their peers,” said Dr. Jennifer O’Dea, MPH, Ph.D., an internationally-known childhood obesity researcher, and nutrition and eating disorder specialist at the University of Sydney, Australia.

According to the CHEAR researchers, their calculations indicated “that 15% of children age 6-11 and 10% of children age 12–17 are obese. [As is the girl to the right.] Overall, 25% of children age 6-17 are either obese or overweight.” These figures are a problem, the researchers noted, because they are lower than the national prevalence, which they claim is 35%. This mismatch was used to suggest that parents “under-estimated their children’s weight and/or over-estimated their children’s height in response to this poll.” This was the first strike against parents, implying they are not to be trusted or to be capable.

Among the children, aged 6-11, the researchers had calculated as “obese,” they found more than 40% of their parents thought their child’s weight was “about right,” only 13% rated their child as being “very overweight,” and only 7% were “very concerned.”

As the children entered puberty and their teen years, even though the actual numbers of young people calculated as “obese” were one-third lower than the younger ages as they grew, weight became a bigger issue among parents. Among the young people age 12-17 labeled “obese,” 31% of parents rated their child as “very overweight” and 46% were “very concerned.”

Note: This concurs with other studies finding that the natural rapid fat and weight gain in pubescent girls, as their bodies prepare for childbearing, is often mistaken by parents as “getting fat,” triggering dieting and increasing risks for eating disorders.

Action points

In describing the implications of their poll, the researchers began:

It is very apparent from these results that there is a stark mismatch between children’s obesity status and parents’ perceptions of whether their children’s weight is appropriate for their height, especially among parents of obese children 6-11 years old. Parents who do not recognize obesity in their children, or who are not concerned even if they do recognize obesity, may be less inclined to help modify their children’s diet and physical activity patterns. Without parents’ help, school and community efforts to mitigate the childhood obesity epidemic may have limited success.

This isn’t the first time parents have been accused of failing to recognize that their children are fat, or of being in denial and lacking appropriate concern for their children’s "obesity" problems. In “By whose definition?” we learned of similar studies reporting that parents and adults are unable to identify children who are purportedly overweight, per the BMI growth charts. But is this a problem with the parents or the measure? Despite popular portrayals of the most extreme examples as representative of “childhood obesity,” most such children and teens aren’t remotely what parents or doctors would think of as obese. The smallest changes in height or weight as children grow is all it takes for them to cross the line and join the rosters of those labeled as “overweight.” And rather than acknowledging that the BMI-based labels are untenable, parents are being indicted.

Parents who are poor, minority or without college degrees are especially looked down upon as less concerned parents, lacking the knowledge or ability to feed their children correctly or provide them opportunities for activity. Two findings in this very poll, however, negated these popular misperceptions. First, BMI levels for all ages of children, they reported, “did not differ by parent education, household income, or children’s insurance status.” Further, 41% of blacks were ‘very concerned’ with their ‘obese’ children’s weight compared to 30% of whites.

In interpreting their poll, they go on to conclude:

Health care providers can play an important role in helping parents to recognize obesity, and take steps to modify a child’s diet and activity levels. The National Poll on Children’s Health found that the vast majority of parents of obese children believe it is very important for doctors to address obesity with adolescent patients during routine check-ups.

Here again, they provided no evidence for their opinion that doctors can or should help identify fat children and intervene. Nor did they provide evidence for the effectiveness of their suggestion to modify a child’s diet and activity levels. The U.S. Preventive Services Task Force had concluded there is insufficient evidence to recommend routine screening for overweight in children and adolescents as a means to prevent obesity or adverse health outcomes. It had also concluded that “a substantial proportion of children under age 12 or 13, even with BMIs above the 95th percentile, will not develop adult obesity.” Nor could the USTSTF find good evidence that behavioral interventions (diet and activity) for overweight in children and adolescents improves health outcomes or physiological measures, such as blood lipids (“cholesterol”), glucose tolerance, blood pressure or physical fitness. The USPSTF concurred with the American Heart Association’s 1996 Scientific Statement for Healthcare professionals in concluding there was no evidence that any interventions to reduce or prevent childhood obesity — no matter how well-intentioned, comprehensive, restrictive, intensive, long in duration, and tackling diet and activity in every possible way — have been effective, especially in any beneficial, sustained way.

Not surprisingly, JFS has reported on numerous childhood obesity initiatives that have all proven ineffective, such as here, here, here, here, here and the most massive program in the country here.

And what about the possible harmful effects of subjecting children to labeling and weight control interventions? Dr. Davis and colleagues made no mention of those. Yet the six-member Childhood Obesity Working Group of the USPSTF, when it released its latest ruling, published strong condemnations of clinicians and professional organizations that support BMI screening of children and childhood obesity interventions, none of which have quality evidence.They admonished:

The first principle of medicine is well known: primum non nocere (first, do no harm)....

[W]e have little information about the potential harms of screening, such as labeling, reduced self-esteem, poor eating habits, eating disorders, adverse family relations, or the effects of continuing to lose and regain weight (yo-yo dieting).... If we forge ahead with an intervention (whether therapeutic, preventive or even diagnostic) without knowing whether it is beneficial, we run the risk of causing unintentional harm.

What’s up?

Whenever we encounter a paper where the conclusions and recommendations are so divergent from the evidence, especially when they resort to tried-and-true marketing techniques rather than clinical studies, it behooves us to look at the source and consider what the paper might be promoting.

The lead author and director of this C.S. Mott Children's Hospital National Poll on Children's Health, Dr. Matthew Davis, received his M.D. from Harvard Medical School and his postdoctoral training there and at the Robert Wood Johnson Clinical Scholars Program at the University of Chicago, Illinois. He joined the University of Michigan as an assistant professor and faculty of the Robert Wood Johnson Clinical Scholars Program. He’s been the Co-Director of the Robert Wood Johnson Clinical Scholars Program since July, 2006.

He was also the lead author of the “Guidelines for Prevention of Childhood Obesity” section and a member of the “Expert Committee on the Assessment, Prevention and Treatment of Child and Adolescent Overweight and Obesity”.

Those “Expert Committee Recommendations Regarding the Prevention, Assessment, and Treatment of Child and Adolescent Overweight and Obesity” were published last week as a supplement in the journal Pediatrics. Coincidence?

JFS readers need no introduction to these far-reaching guidelines or to the expert committee, as both were reviewed this past summer when their proposals, making doctors veritable lifestyle police, were first posted on the AMA website. Their recommendations included redefining “obesity” and “overweight” in children, and having healthcare providers subject all children with BMIs > 85th percentile to routine assessments, blood tests, and comprehensive monitoring and recording of the children's and their parents' lifestyles.

Every well-child visit is now to include a qualitative assessment of eating behaviors, which is to include identifying how often the family eats meals away from home, consumption of sweetened beverages, portion sizes, how often and what children and teens eat for breakfast, how much fruit juice is drunk, how many fruits and vegetables and foods high in fat or calories are eaten, and the frequency and types of snacks.

Each pediatric check-up is also to make a determination of physical activity which is to include “at a minimum” if the young person is meeting recommendations for 1 hour of moderate to intense physical activity everyday and, if not, why and what social, environmental or familial situations are standing in the way; and how many hours they watch TV or videos, play video games and use the computer, to ensure screen time is less than 2 hours a day.

Every child deemed “overweight” or “obese” by these new standards should have a complete work-up for “obesity-related risk factors” — one more appropriate for an elderly, ill cardiac patient. These children will be forced to visit the doctor more frequently for increasingly intensive multi-disciplinary interventions, tests and monitoring. The restrictions on the behaviors of both the children and the parents become stricter if the children don’t lose sufficient weight. Doctors must monitor for unhealthy behaviors and convince families to modify their behaviors. The desired outcome is to get all children’s BMIs <85th percentile. Healthcare professionals are also to become active in supportng school and community childhood obesity initiatives.

The 126-page recommendations, when carefully read, reveals no evidence in support of their recommendations. As the document says:

Virtually no clinical trials examining the effects of any specific dietary prescription on body weight or adiposity in children control for the effects of potentially confounding factors, such as treatment intensity, behavioral intervention strategies, and physical activity. Although comprehensive approaches aiming to modify diet, physical activity, family behavior, and the social and physical environment are undoubtedly needed, studies involving multiple modalities cannot assess the efficacy of any specific component. In the absence of data on the relative efficacy of various dietary prescriptions in the treatment of obesity in children, it is sometimes necessary to make inferences from the childhood obesity prevention and adult treatment literature....

Addressing childhood obesity requires a comprehensive holistic approach. Although the evidence is limited, increased physical activity alone has not improved children’s weight status substantially....

It remains to be seen if doctors and pediatricians will choose to ignore the evidence against the need to worry about the health of growing children based on their BMIs and the evidence against screening for “obesity” or “obesity-related” health indices. It remains to be seen how many doctors and parents will want to expose their kids to obesity interventions with no credible evidence for effectiveness and with potential harm.

© 2007 Sandy Szwarc

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