chickenfeet

I'm overweight but not by much. I weigh 213 pounds which at just over 6 feet tall gives me a BMI of 28.5. I would like to be 200 pounds (BMI=26.7) which would apparently make me still overweight. Frankly this is nuts. I was 200 pounds when I was playing rugby competitively and was as fit as I've ever been in my life. It's not like I'm unfit now. I've run 25km in the last four days which is more than a lot of people do in a year. What's really scary is that according to the BMI calculation I could be 140 pounds and still be a healthy weight! When I was ill about ten years ago I dropped to 155 pounds and I looked horrible, all skin and bone, and not in the least healthy.

So let's look at this in the context of the "obesity epidemic". It's trivially obvious that the BMI statistic exaggerates obesity among tall people and does the opposite for short people (weight, other things being equal, is proportional to the cube of body weight rather than being linear). It's a fact that in the developed world average height has been increasing for at least a hundred years. This of course means that obesity statistics based on BMI will get worse even if nothing is happening! I'm not saying there isn't a problem but it is being exaggerated by the use of a very dubious statistic.