How much do you trust the BMI

I think it's basically crap.

I think it's basically crap.

^ This.

BMI is crap for a lot of people.

Athletes with super low body fat and lots of muscle can be considered obese according to their BMI because, although it does give a range to account for some difference in frame size, it doesn't take into account body fat %, lean muscle mass, etc.

According to my BMI, I'm at the top of the "healthy" range - around 24; however, I have not been overweight for at least 15-20 pounds (according to my doctor).

The BMI stole my wallet

The BMI stole my wallet

No, that was me.

I think it's useful for most of the general population (in other words, not bodybuilders, just average people) as a blunt tool for measuring health. A very rough estimate, if you will.
Body fat % is obviously better, but I think BMI is okay as long as you don't put too much stock in it.
My BMI at the moment is 26.9, in the low end of overweight. I think this is a point or two high because I have a fair amount of muscle.

Not at all. Once I hit my goal BF (18%), I'll still be 10 lb over the "healthy range" for BMI.

I learned in my Epidemiology of Obesity class, that BMI is best for population level comparison, but NOT for the individual diagnostics.

I was talking to my doctor about it and he said he thought it was a bunch of crap as well. He was explaining that it doesn't take into the equation of a persons body type. I was concerned because the bmi was telling me I was obese and he said he would not put me at that level. He said I could use to lose some weight, overweight but not obese. I'm 5'7 and was 198 at the time of the conversation. So no I wouldn't put a lot into BM.

I think when you first start this process its a good indication of how low you can safely go (cuz lets face it, there are some people that have unrealistic, unhealthy goals of 100lbs when they are 5' 10' for example) BUT once you get close to where your range should be you need to re-evaluate and start going off of body fat percentage and stuff like that. If you are building muscle then BMI does nothing for you.

To clarify: Don't totally base your loss off of it.

I think when you first start this process its a good indication of how low you can safely go (cuz lets face it, there are some people that have unrealistic, unhealthy goals of 100lbs when they are 5' 10' for example) BUT once you get close to where your range should be you need to re-evaluate and start going off of body fat percentage and stuff like that. If you are building muscle then BMI does nothing for you.

I agree with this. I definitely don't think it's "crap" for the average person, it can be a helpful tool.

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.

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.

The BMI stole my wallet

Lol lol lol

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.

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).