Hi folks. Haven't had time to read or post much lately, but here's a couple 
quick items. 

(1) Regarding the BMI discussion, and Pat Naughtin's Metrication Matters 59: As 
a rule of thumb, dropping the 1 and the decimal to give your ideal body weight 
might work, but BMI itself is, in my opinion, a very crude measure at best. 

For myself, 1.70 meters tall and a mass of 90 kg, my BMI works out to be 31.1, 
which says I am obese (I am not). Pat's rule of thumb says I should weight 70 
kg. 

Here's the problem: I have a much lower inseam-to-height ratio than most 
people; my inseam is 70 cm, giving me a 41% ratio; typical is 45% to 48%. So, 
shopping for pants in the USA I need a 34" waist (hardly obese) and a 28" 
inseam. Nearly impossible to find. 

Since torso obviously has a much greater cross-sectional area than legs, short 
legs means greater ideal body mass, and throws off the BMI. Even my doctor 
wonders at my weight when I step on the scale -- he expects to see 180 to 185 
lbs (yes, he uses colloquial units) and I weigh in near 200. 

A far better measure of obesity is simply percentage body fat. This can be 
measured reasonably accurately on modern electronic scales. I come in around 
18%, which is a tad high, but a long ways from obese. 
(http://en.wikipedia.org/wiki/Body_fat_percentage) 

FWIW, my ideal weight is around 78 kg. 

(2) Was in CostCo the other day, and noticed a bathroom scale with a glass 
platform. LARGE sign reads: Fully 10 mm Thick Platform! No colloquial units 
anywhere. I remain convinced that the USA is slowly undergoing a "stealth" 
metrication. Slow but sure. 

Jim Elwell 


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