I was thinking today about the BMI Scale. About how, according to proponents of this scale (who currently include most doctors), all humans should fit into a very narrow ratio of weight and height in order to be considered normal (and, somewhat inexplicably considering the complete lack of causal proof, healthy)
And I thought, surely if this is the case it will be born out in the rest of nature. So I started with animals, horses to be exact:
Pardon the pun but Whoa Nellie! Those horses have drastically different sizes, and height/weight proportionality – yet they are all considered normal and healthy (indeed – these are the models of perfection) for the type of horse they are. Or maybe it’s just that nobody really speaks “horse” and so we can’t tell the Shetland Pony and the Shire that they need to cut down on the hay and run a few more laps of the pasture until they look like the Arabian. I wonder if donkeys are sad that they get left out of this chart?
So then I looked at vegetation. I thought that maybe with horses I’d looked at too broad a spectrum and that in this case I’d just look at broad leafed trees.
So then I looked at minerals. Surely in the hard and fast (I’m on a roll with these puns – sorry) world of tourmaline we will find a model of the narrow scale of size to which we are holding humans.
You have got to be kidding me! Look at all that size diversity. This proof of BMI across nature thing isn’t working at all! (If rocks could talk do you think they’d be foolish enough to ask “does this moss make me look fat?”).
So surely it must at least be consistent in humans. Feet for instance, if human bodies are supposed to fit into a narrow range, then surely our feet will too.
Did you know that men’s shoe sizes go from size 3 to size 20 with widths from AAAA to EEEE?! And don’t even get me started on various arches and toe lengths. So you can be a 3 EEEE (short and wide) with your big toe as your longest toe, or a 20 AAAA (long and thin) with your second toe as your longest toe, and we think that’s just fine. In fact, about sixty percent of people don’t even have two feet that match – one is bigger than the other. But if your body is short and wide then clearly there is something wrong with you.
So once again I say that using BMI as a measurement that tells you anything other than the ratio of someone’s weight to their height is crap. If you want to talk about health, then use some measures of actual health. If you want me to believe that I can’t be healthy until I fit into a very narrow size range then take a hike (and look around at nature while you do it).