Debbie says:

In a New Year when Haiti was devastated (yet again), this time by a huge earthquake, the Democrats threw away a sure thing (yet again), and the Supreme Court asserted that corporations are more important than you and I (yet again), it’s not too surprising that Michelle Obama’s choice of a new cause didn’t get too much pixel attention. But here at Body Impolitic, we feel compelled to notice that First Lady Obama is formally taking up the torch of the nonexistent “epidemic of childhood obesity.” Yes, yet again.

Calling obesity an epidemic and one of the greatest threats to America’s health and economy, first lady Michelle Obama said Wednesday that she would launch a major initiative next month to combat the problem in childhood.

2010: It’s just like 2009, except less original.

First things first: there is no epidemic of childhood obesity. Yes, I know you’ve read about it in hundreds of articles, seen it on dozens of billboards, had thousands of office or street-corner conversations about it. Nonetheless, the emperor (or perhaps the First Lady) has no clothes.

Here are the 2008 numbers, an 8,000-person study published in the highly respected Journal of the American Medical Association:

Results Because no statistically significant differences in the prevalence of high BMI for age were found between estimates for 2003-2004 and 2005-2006, data for the 4 years were combined to provide more stable estimates for the most recent time period. Overall, in 2003-2006, 11.3% (95% confidence interval [CI], 9.7%-12.9%) of children and adolescents aged 2 through 19 years were at or above the 97th percentile of the 2000 BMI-for-age growth charts, 16.3% (95% CI, 14.5%-18.1%) were at or above the 95th percentile, and 31.9% (95% CI, 29.4%-34.4%) were at or above the 85th percentile. Prevalence estimates varied by age and by racial/ethnic group. Analyses of the trends in high BMI for age showed no statistically significant trend over the 4 time periods (1999-2000, 2001-2002, 2003-2004, and 2005-2006) for either boys or girls (P values between .07 and .41).

If that’s too many numbers for you (it’s right on the edge of what I can follow), here’s the paper’s conclusion:

Conclusion: The prevalence of high BMI for age among children and adolescents showed no significant changes between 2003-2004 and 2005-2006 and no significant trends between 1999 and 2006.

Oh, and if this wasn’t enough, 1999-2000 is when they changed the growth charts to reflect BMI, a completely useless measurement:

But the growth charts underwent a significant change in 2000 which has made them even more controversial. The new charts, issued by the CDC in May 2000, were based on BMIs, rather than weights and heights. … What didn’t make the news and few parents may know is that the new BMI-based growth charts meant children’s percentile on the growth curves changed. With the new charts, nearly two-thirds of children were suddenly at higher percentiles, with greater discrepancies among shorter children.

So even if kids are too fat (which they aren’t; keep reading), it’s not an epidemic, because it’s not growing.

Second, and perhaps more important, if there was a childhood obesity epidemic, none of the standard plans to counteract it have the least effect.

The U.S. Preventive Service Task Force, which reviewed nearly 40 years of evidence on screening and interventions for childhood and adolescent overweight — some 6,900 studies and abstracts … concluded that there is no quality evidence to support that overweight or obesity in youth is related to health outcomes or predicts fitness, blood pressure, body composition or health risks. The USPSTF found insufficient evidence to recommend routine screening for overweight in children and adolescents as a means to improve health outcomes. It did, however, note potential harms of screening programs. According to the USPSTF Childhood Obesity Working Group, no scientific review has been able to find quality evidence that any program 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 — has been effective, especially in any beneficial, sustained way. Nor has any program been able to demonstrate improved health outcomes or physiological measures, such as blood lipids (“cholesterol”), glucose tolerance, blood pressure or physical fitness. Nor has any diet or exercise intervention in children been shown to lead to better health outcomes in adulthood. Not only did the USPSTF find no evidence to support the effectiveness of counseling for healthy eating in young people, it also found no evidence to support low-fat diets in children and, instead, found growing evidence for harm.

(If you click the link to the findings, be warned that the abstract is *ahem* not representative of the study’s findings. See “The Faith Sentence.”)

In a nutshell: the First Lady has picked a mythical cause which, even if it were real, supports no evidence of a problem, and no approach to the non-problem that has ever shown the slightest effectiveness.

Just think about the things she could be focusing on.

I think I’ll send a somewhat politer version of this post to her in a private letter.

A million thanks to Sandy Szwarc at Junk Food Science, where all the facts I need are always in one place. And Lynn Kendall was first with the pointer.