Meet Lauren

One of our intrepid members (jamiedory) tweeted me on November 24 to ask me to sign Lauren's petition at change.org. I did and retweeted the request to my followers as well. Seventeen Magazine had come out with a truly unscientific and shockingly thin-skewed ‘healthy’ BMI range and Lauren petitioned to have them remove it.

She succeeded and on December 1, 2012 Seventeen had taken down their online BMI calculator.

How excited am I? Truly thrilled!

Why Is This Important?

There is no such thing as a de facto healthy or unhealthy BMI range.

“Normal body weight is distributed in a bell curve like height. Most media promote an unhealthy thinness or impossibly lean muscularity. The narrow range suggested by insurance company tables or other charts for individual weights are often used inaccurately. These weights are averages, not norms.” 1

Bell curves identify a range, and when considering human attributes such as height or weight, perhaps only the furthest points of a bell curve may involve any negative health impacts at all. If you are exceedingly tall (beyond about 8 feet in height), then your life expectancy is negatively impacted. And in fact mortality rates for height are more severe for the tallest at the right hand end of the curve when compared to the shortest at the left hand end. However, the opposite is true when it comes to weight you see on the bell curve below (expressed as body mass index, or weight over height squared): mortality is more severe for the thin than the fat.2,3

If BMI 26 were truly unhealthy then our life expectancies would be dropping right now, and instead life expectancy has increased by four years in the past 25 years alone (Centers for Disease Control, 2012).

So if more than half of our population is naturally “overweight” then who decided to call it “overweight” and not “average weight” given that BMI identifies averages and not an optimum or a norm? I go into a lot of detail on this in the Fat Series, but suffice to say the 1998 NIH Panel on Obesity chaired by F. Xavier Pi-Sunyer had two questionable studies upon which they based their decision to shift the markers of “over weighted-ness” to within one standard deviation from the mean (the peak of the bell curve) and that is already a marked departure from the accepted application of statistics.

Furthermore, the committee members’ involvement with the weight loss indsustry as well as the pharmaceutical and medical device industry focused on obesity interventions (all but one of the committee members had some conflict of interest along these lines) suggest that calling ourselves overweight rather than average may have more financial rather than health value driving the skew in our understanding.