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Put the BMI to bed

Well, it’s about time. Finally, a comprehensive study showing that hip to waist ratio measurement is a more accurate predictor of heart disease the the body mass index.

I have found all the recent talk of the “obesity epidemic” quite disturbing. It’s almost as though we have forgotten all about teenage girls’ eating diorders – and don’t seem to really be noticing that the boys are starting to catch up in this department too. The pendulum has swung from skinny-is-bad to fat-is-bad, and it’ll be just a matter of time before it swings back again, I fear. Furthermore, when people start to link the increase in obesity with smoking cessation campaigns, it seems the war on obesity has the potential to take people to some weird & disturbing places indeed – hey, I may be giving myself lung cancer, but at least I’m a twig. I’ve wondered for quite some time now just how much of the “obesity epidemic” has to do with the skewing of the data that occurs when you use the BMI.

For those of you don’t know me, I’ve lost some weight, give or take about 20 pounds. While before I certainly felt I could lose a little weight, I certainly didn’t feel that I was unhealthy, and the curves were still looking OK. The musculature was well padded, but still substantial, and my athletic performance was pretty good and improving steadily. However, my BMI indicated that I was obese. My doctor told me I was obese by looking at her computer screen, not by looking at me – boy, was that ever a strange day. Now, a bit lighter, I don’t feel too much different (OK, my yoga practice has improved dramatically!) although the complements I get are nice. But my BMI still puts me just shy of obesity – in the “your-weight-could-lead-to-health-problems” range. Loosing 20 lbs brought me down one and a half points only. If I didn’t know any better, I’d be on the weight loss fast track, and probably really hurting myself in the process. Fortunately, I have the brains to look in the mirror, see that I’m fit and toned (& can even see a couple of ribs), decide I look OK and that my doctor is a flake and not worry about it. Impressionable teenagers may not be so lucky.

I won’t deny that we might have a problem. But so long as the true scope of the problem is masked with inaccurate measurements, and those measurements result in inappropriate assessments at the indivudual level, we’re just going to replace one problem with another.

2 Responses to “Put the BMI to bed”

  1. You are so right, when I lived in Michigan I TA’d a human physiology class one summer, and the BMI told me I was 20 lb overweight. At that time, I can’t imagine what I would have looked like if I weighed 20 lb less (right now it’s easy, I would look like myself instead of myself with kleenex in my bra and a basketball in my shirt!). The BMI doesn’t take into account things like frame size or muscle mass. It’s a very poor tool.

  2. Interestingly enough, I learned about these results eight years ago in medical school…

    Remember the “apple” and “pear” descriptors? (Central adiposity versus hip/thigh adiposity)? Even over a decade ago researchers were finding a link between having fat in one’s abdominal area (the so-called “apple” physique) increased the risk for heart disease.

    Interestingly enough, males are more likely to have central adiposity (“apples”) compared to us women (who are usually “pears”), which gives us a survival advantage of sorts. Which also begs the question why researchers were comparing apples to pears… (you KNEW a pun was coming) :D

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