BMI - how reliable is it?

[Katharina]

Hi,

I just checked my Body Mass Index, out of curiosity, and found to my great astonishment that I have a BMI of 18, which is supposed to be UNDERWEIGHED! Now, the funny thing is that I am not at all skinny. I mean, I'm not fat either; I would call myself 'slim', but I certainly have some good 'padding' around my undercarriage... (which, though it doesn't exactly drive me into despair, I wouldn't mind loosing either). I'm certainly not the kind of person a doctor would get worried about.

So I'm wondering - is the BMI perhaps a little out of sinc? I mean, I know these formulae have to be adapted to individual built and all, and I am quite a light frame. Also, perhaps I am just lighter because I am so out of shape - after all, muscles weigh a lot more than fat. Still - UNDERWEIGHED?! Lord, that is the first time anyone's ever said that to me, to be sure!

What are other people's experiences with the BMI?

[flymeaway]

I don't think its a very reliable measure of health, to be honest. It might give a general picture - but you were totally right to take in to account your general fitness level and frame (which the BMI doesn't address). For instance a person who is slim but has a lot of muscle might appear to be overweight according to that measurement, and vice versa.

For a more accurate picture of your health get your doc or local health club to find your fat-muscle ratio and check your cardiovascular fitness as well. :grin:

[Paddles_up]

I agree with flymeaway....the most accurate BMI test is the water displacement test. They are expensive and difficult to locate facilities that use that method.