How much do you trust the BMI

Scott613

BMI is like government, it's there but it's a bunch of BS and doesn't really work when you look into it.

blondishandbookish

BMI at a population level is scarily accurate and I think (although am not sure and dont have the papers) that it was intended for use at a population level only.

I have done several economic models for diabetes and CVD over the last 3/4 years using real data for different populations in the UK . (real data for measures including BMI/blood pressure/ hba1c and the resulting consequences - we always modelled the current picture to validate the model - in other words, with the current data, were the outcomes the same.
The higher the BMI, the higher the rate of diabetes/CVD/ emergency attendences etc etc

FWIW, when we were doing these models, we weren't asked to assess whether people were under/over/ideal weights - we were only looking at health outcomes (death/morbidity/ co-morbidities/emergency attendances/seconday care utilisation - outpatient and inpatient.

At an individual level, I would suggest very few people as a proportion of the population are outliers to the point where it doesn't apply (elite rugy/rower/bodybuilder); for most other people, the ranges are wide enough to apply.

Huffdogg

If there's a term that describes a number less than "not at all," then that's how much stock I put in it.

MJ7910

it depends more on how you look and your measurements. BMI is just a general tool but doesn't really take body fat percentage into account.

honeysprinkles

I've posted this a few times, and I have a feeling the nobody actually reads it, but I'll try again.

http://www.npr.org/templates/story/story.php?storyId=106268439&sc=fb&cc=fp

I really don't think it's that bad. For the average person, it provides a pretty wide range of generally healthy weights. I just think people take it for more than it is and attribute more meaning to those numbers than was originally intended.

andlovesaidn0

The BMI stole my wallet

Lol lol lol

rileamoyer

I know that the BMI calculator here is just an estimate based on averages. I am an pretty average person I guess. I had a full body comp done at my health clinic in May - My BMI there was less than 1/2 point different the MFP's estimate.

ahamm002

BMI at a population level is scarily accurate and I think (although am not sure and dont have the papers) that it was intended for use at a population level only.

Yes, it was designed for use on populations, not individuals. BMI is not supposed to be accurate for individuals. Sure, it might be accurate for some people, but how do you know if that's you? You don't know, so don't use it. I supposed if you were stranded ona desert island and didn't have any other way to measure body fat %, then you could justify using it.

Tujitsu56

BMI has nothing to do with the individual from what I understand. It's just an average for people your age and height. Doens't factor in muscle mass, bone density, or anything of that nature. Everyone is sooo unique so w/o getting actual measurements, it's hard to tell. I barely trus other body fat measurements for that matter. My favorite thing to go by is the mirror and my fitness levels.

HealthyBodySickMind

I've posted this a few times, and I have a feeling the nobody actually reads it, but I'll try again.

http://www.npr.org/templates/story/story.php?storyId=106268439&sc=fb&cc=fp

There, I read it

Quick summary for those that didn't: BMI was never meant to work for one person, only for a population, and it's skewed so that it only works (and only as a mediocre generalization) for a population that is mostly sedentary (so adequate for, say, USA overall population).

HeidiMightyRawr

I say for the average person with normal muscle mass it can be a useful "guide". Just that though, a guide - not the be all and end all. I've heard of it being used in schools and perfectly healthy kids are being told they are overweight/obese and letters sent out to their parents etc. Common sense needs to be used, as well as your own eyes.

For me at my highest weight I was a BMI of 23. I wouldn't say I was fat but it definitely was too big for me. I feel most comfortable at the lower end, around 19/20 but that could well change if my muscle mass increased.

cofakid

i find it frustrating that so many ppl say bmi is bs because if your lean and fit it will be totally wrong. The reason i find it frustrating is ppl just say oh bmi is bs dont go by that but i KNOW i am NOT lean, i am NOT fit, and for me the bmi is a good starting point. I know im overweight from what ive been told by doctors, and bmi gives ppl like me a starting point. i know it doesnt really apply to lean fit people, but for most people who are trying to lose weight its a good starting point. and i think telling people over and over again that bmi is bs makes people think oh my bmi is obesse but everyone says thats bs so i dont need to lose weight when in fact they do. thats just my opinion anyway.

Elleinnz

I've posted this a few times, and I have a feeling the nobody actually reads it, but I'll try again.

http://www.npr.org/templates/story/story.php?storyId=106268439&sc=fb&cc=fp

Great article !!

lord_lethris

BMI is boll**ks. Throw it, its different for everyone, and most of the calculators/rules you find online or in books are rubbish.

I got my BMI done by both a qualified fitness trainer and a Doctor. They both used an electronic machine that (by my knowledge) measures the fat/water lvls (or something like that, I don't really know). The both gave me the same result...

...Which was different from the one I calculated using a BMI rule in a Weight watchers book.

The BMI rule from Weight watchers told me im overweight.

The Doctor said that even though I could do with loosing some weight around the waist, im not "overweight" due to the weight of my bones and muscle (or something to that tune).

conclusion - If you are going to worry about your BMI (even though its Boll**ks), get it done with the right equipment. its free, and you get a TRUE reading.

Lyadeia

I personally think it's crap.

In response to cofakid's frustration, I would simply offer that perhaps you should measure something else like body fat percentage instead of BMI simply because no matter how large or small you are, it gives you a much more realistic view of where you are with your progress across the board. BMI is often flat out wrong with lean people, but body fat % is much more true for anyone who tests it correctly. I would rather see the progression of a measure that is more accurate for everyone than just people currently my size.

meowy12

It Blows

mikeyrp

BMI stands for "Body Mass Index".

I have some other suggestions:

Bollocks, Mostly Inaccurate
Badly Misinformed Individuals
Basic Moronic Information
Badger My Intestine
Bottom Maggot Indicator

All of which is about as useful as the measure itself. Take a look at the my picture: I'm fit, average build, average height and I'm right at the very top of the normal range!

dreamshadows

It's a highly questionable system.

lormc

But, but the Wii Fit tells me that I am overweight and have to lose another 20 lbs to reach my ideal BMI! However, anyone that knows me, tells me that my weight loss so far is fantastic and not to lose too much more....

Which should I believe?

quepastaaa

Not so much, personally.

I went over both with my doctor. He said that if I lost enough weight to put me in the "healthy BMI" range, that it would actually be far too much. Turns out that according to the BMI I'm obese, but by body fat % I'm actually just overweight.