Friday, September 6, 2013

Fun Fact Friday: BMI is a Joke

I decided if I had some hybrid activist-academic purpose to my writing I might actually DO more writing. SO my goal for the rest of the year is to bring you useful information that is readily available but OVERLOOKED by damn near everyone, but especially the media.

Right now I'm really, really energized about fat politics and activism, particularly because it has direct affects on my favorite topic which is radical body love. So for the next couple of weeks I'm going to do some deconstructing of our common "knowledge" about health, fatness, dieting, and body shame. This is nothing new. Lots of people have written about this before but many of my non-fat-activist-academic friends probably won't read 783 books, articles and blog posts I give them as references but they WILL (hopefully) read my words here on my blog. Also I'm only going to tell you the shit I find most compelling and in the order I feel like it makes most sense. Others may think other things are more important or may tell you things in a different way, but this is my blog so I'm going to do it my way. And now, with my signature voice and style, I'm about to break some shit down for you.

On today's menu...

The history of the modern day BMI chart! I know, titilating. But we have to start somewhere and before I can start blowing your mind with ideas that go contrary to everything you hear on the news every day about fat & health we have to start with a little history lesson. So pour yourself some coffee, water, alcohol, or any other beverage of your choice. Let's get started shall we?

BMI charts were first consistently linked to health outcomes in 1912 by life insurance companies (though they were called something else). Uh what? Over a hundred years old and thought up by insurance companies and not doctors? Need some perspective? Penicillin was discovered in 1928. We're using a health rating scheme that is pre-antibiotics. Sound ridiculous? It is. 

Here's a really boring article about how many ways we've measured fat over the past 100 years: If you don't feel like reading it, cool. Let's just suffice it to say that the sheer number of ways it has been done and why is mind boggling. But also, for me, points out how flawed the system has always been, and continues to be.

The modern BMI chart was conceptualized and advocated for by Ancel Keys in 1972. NOTABLE in his publication is that he says straight up that: 
Populations differ from one another and populations change. Average values for weight and height for given age and sex for a given population do not necessarily apply to other populations or even to the same population at another time. Further, there is no present prospect of obtaining for any population true average values of weight for given height, age and sex. Certainly persons examined in connection with application for life insurance are far from being a random sample of the population.
Additionally he notes: 
In recent medical literature the so-called ‘ideal’ or ‘desirable’ body weight is often used as a basis of reference, the relative body weight then being expressed as percentages of values in the tables published by the Metropolitan Life Insurance Company [42]. Those tables take no account of age; in effect they simply list the average weights of insurance applicants of given sex and height at age about 25 [13-161. As noted elsewhere [43], the use of ideal or recommended weight confounds age and weight because on the average weight increases with age until the fifties while increase in height is over by the early twenties at the latest. The general trend to continue growth in weight may be undesirable but it has no relevance to the question of providing an objective description of relative body mass; it is scientifically indefensible to include value judgement in that description. The characterization of persons in terms of desirable weight percentage has resulted in attributing to ‘overweight’ some tendencies to ill health and death that are actually only related to age [43]. 
SO, the person who created the modern BMI scale is basically saying given the best measurement we can come up with for BODY FAT (not health!) it's still flawed and not a very good measure. Additionally it doesn't give us any information on whether that fat number is good, bad or otherwise. Veryyyyy interesting.

Stay tuned for next week when I tell you about the great BMI scandal of 1998. THRILLING SHIT MAN.

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