More About the BMI

                                                                  
Previously I've written two articles about the Body Mass Index (BMI).
Below is a very wise statement about the meaning of the BMI
by a member of one of the forums I frequent.

"Well, here's the thing:
there can be a difference between "heavy" and "unhealthy".
Not everyone who is over the BMI range labeled "normal"
is necessarily an unhealthy, unfit specimen.

This is just a natural result of using population-level averages
to define arbitrary cutoff values: of course any given individual
may have differences from the overall average!

I don't quite think BMI is bad science, in itself:
it's just a number, after all.
It's how it's used that can lead to trouble.

The BMI charts, which are really just fancied-up height/weight tables,
are supposed to offer a first-glance idea of whether you are "likely"
to have a suite of health problems associated with being overweight.

But ideally, if you've got the individual right there in front of you,
you could take a "second" glance and see if the person really does
have the health problems "correlated" with being in a certain range.

One could check out their heart, measure their blood numbers
for things like cholesterol, etc. -- you don't have to "guess",
when you've got a person right there.

(But, alas, medicine as practiced currently does tend towards
the easy, look-it-up-on-a-chart approach,
and all too many doctors never go beyond that.)

And as I say, it's quite possible for someone to be outside
the chart range but not unhealthy in these other ways
(and vice versa: BMI in the normal range
is not an automatic guarantee of health!).

So yeah, I'd think that one shouldn't panic about being a bit
outside the range that The Chart says you should be in,
if you're otherwise fit and healthy.

At the same time, if you've got a BMI in the 30s,
you probably don't really need The Chart to tell you
that you may have a problem with your weight."