BMI unreasonable?

Anyone else feel the BMI calculators out there are just unreasonable? I looked at a few today that said my target weight should be around 107lbs. That is like celebrity anorexic for me! When I was in the military, after basic training I weighed 180 lbs. I was a good healthy weight and size, felt great and all. If I went to 107 I would be all bones. I love my bones but other people don't need to see them all. I have a stocky frame, even for a woman. Apparently even the 180 comes in a grossly overweight. I hate to say it, I was not over weight after basic. I was nothing but lean muscle.

Anyone else find the BMI calculators very unreasonable?

Absolutely. Anybody with a lot of muscle mass is going to have a high BMI. Body fat measurement is more accurate. My BMI says I am "grossly overweight" as well, and while I definitely have some fat I can lose, I definitely cannot see myself weighing any less than like 150-160. I'm short but have a broad frame... broad shoulders, broad hips, etc., and very muscular legs. If I weighed less than that I'd start looking sick, I believe. I say ignore the BMI and just make sure you feel good and your clothes fit.

BMI is horribly inaccurate. It is only useful when averaging over hundreds or thousands of people. For your own fitness tracking body fat percentage is good, but body fat distribution is the best indicator by far. Research shows that stomach and visceral fat is the most harmful for health, so reducing that as much as possible is the goal most closely related to optimal health. For people who tend to store fat in the thighs or buttocks, they will invariably have a higher body fat percentage than people who tend to store fat in the stomach area. Men tend to gain fat in the stomach area while women in the thighs or buttocks, which is why men tend to have lower body fat percentages than women (and lower optimal body fat percentages).

I used to think BMI was unreasonable until I got mine down to 23. Now that it's there I've never felt better in my life.

My range was something like 107 to 147. But even at 147 I'd still be a lot of bones. I'm glad to hear everyone else agrees though. Makes me feel better. I'll start looking at the body fat percentage thing instead. Thanks!

Yes, I definitely do recommend checking body fat instead. My goal is over the top of the BMI chart for me (by about 7 lbs, but still), but I should look pretty good then unless my body fat calculations are way off.

The 107 means that someone who's your height but has a small-boned and slender build could be down to 107 before they're considered 'unhealthy'. Someone who's your height and built 'slender' could be overweight at 145 and still have a 'normal' BMI, whereas you (judging by your self-description) would be seriously emaciated if you DID make it down there alive. I'm the same way -- my lean body mass is higher than the low end of the charts for me :P

BMI is a useful starting point for many individuals, but people who are outside the normal range and feel otherwise healthy and fit should get a second check using something else. BMI says I'm still overweight, but waist-to-height ratio and body fat percentage say I'm at the high end of healthy.

That being said -- you've still got a ways to go before your first goal, right? Why not get there and then re-evaluate? That's my plan -- it's not like I'm going to diet much differently if my aim is 190 or 180 or 170, I'll just stop sooner if I feel I'm good there.

I agree with those who say it is useless and disagree with those who say it is a good average, starting point or range. It isn't. It is very inaccurate, as in one study I read it misclassified almost half the people in the study. That's way too inaccurate to be useful, you could get similar results by flipping a coin.

I actually don't think the real problem is that it classifies super-fit people as being overweight or obese, while its frustrating people know if they're fit and healthy. It is actually more inaccurate at underclassifying people as "healthy" who have an unhealthy amount of bodyfat, but really low LBM. So you have people who have the double problem of too much fat and not much muscle being told they're healthy.

Wow, how tall are you and where was the calculator that said 107 lbs? I'm 5'8" and 118 lbs, most BMI calculators sneaks me in as just a teeeeeeny bit underweight and tell me I could weigh up to 150/160. It sounds like somebody either made up their own formula or screwed up the programming on the one you used.

I wouldn't use a BMI calculator to pick a goal weight, but it's (usually) not a bad place to get a general sense of your progress.

wookiemouse wrote: »

There's actually a movement to get rid of them completely - body fat percentage is much, much more reliable. BMI becomes grossly inaccurate in anyone who has a muscular build - if you went with BMI, then Michael Jordan was considered obese in his prime!

don't need a movement, just don't pay any attention to them.

Soltari675 wrote: »

Wait a minute ...

BMI will give you a *range*. In order for 107 to be the top of the range, you'd have to be 4 feet 7.

107 is the very bottom of the range for someone who's 5 feet 3 or 5 feet 4 (depending on whether you use 18.5 or 19 as the boundary). You are NOT supposed to be the smallest number in the range! If you're taller than that, then something was wrong with the settings you used.

Now, if you're muscular/large framed, it still might be low, but not THAT low.

My range was something like 107 to 147. But even at 147 I'd still be a lot of bones. I'm glad to hear everyone else agrees though. Makes me feel better. I'll start looking at the body fat percentage thing instead. Thanks!

BMI is good for people who don't know their body fat percentage and are not about to have it measured. BMI at least gives them some indication on where they fall in comparison to others of the same height.

No doubt that measuring body fat is more meaningful. The problem is that only people who are doing something about changing their body composition are likely to ever have their fat percentage measured. For the rest of the population, the majority of people, BMI can be a wake up call.

It's impossible to tell without knowing your height, BMI starts becoming a problem if you're either very tall or very muscular. try my body gallery to get a better understanding at how you would look like at a certain weight. Usually people who are extremely overweight and believe I was in that camp, its hard for us to fathom being even thinner when we lose weight, I'm 6'4" when I hit 245 lbs from 318 I thought that would be enough and that I looked gr8 for my height at 225 I thought for sure I wouldn't need to lose, a healthy BMI for me is 207 and I don't think I should stop there, once you start losing weight and adding defenition, you'll start to recognize that yes indeed you can have a smaller BMI

Soltari675 wrote: »

Even at 180 it says obese. And I most certainly wasn't. I felt great, was all muscle, and well, looked good! lol I was skinny, but not so much you could see all my bones. You could see all the muscles though. I did look at the body fat percentage thing and using measurements and I like those goals a whole lot better. They are much closer to reality.

What? 147 is totally realistic for anyone who's 5'4. The range is supposed to be interpreted with your body frame in mind. If it's actually true that you're bigger boned, I doubt anyone medical would suggest you shoot for the lower boundary.

Also you might be surprised by the actual size of your bones vs what you think they are. If you're a sedentary, unmuscled woman especially, you would need to have bones like TREES for something like 160+ to make sense as an "alternate normal" weight.

I almost NEVER say people are making excuses. But I think you're making excuses. You're using criticisms of the BMI that are legitimate for SOME people as a way of justifying your obesity.

And I also almost never believe in being tough on here. But I think if you're looking to legitimate criticism of the BMI for a reason to stay above 180 at 5'4, if you're a 5'4 sedentary woman, that you need to hear some truth, because you're in denial.

I'm 5'11.5 and was hospitalized at a BMI of 19.8 because my body fat had fallen so low I began to experience life threatening issues. I was so thin I had to wear children's clothes. Now my BMI is 21 and I look very slim, if I were to lose any more I'd be incredibly bony, especially around the shoulders.

999tigger wrote: »

Nope I think its a useful guide and useful if used for the purpose it was intended. People that moan on about it fail to understand what it is and how it came about. Its a guide for general population averages, but it has weaknesses when applied to some individuals. Some mfpers do have a higher degree of muscle than othes. Body fat % is nicer, but its also more difficult to calculate.

OP if you dont believe in its relevance then dont use it.

I fully understand the origin and use of the BMI and its inappropriateness for some people. I am saying the OP is using that legitimate criticism to support denial.

Do you think it makes sense for a 5'4 sedentary unmuscled woman to be 180?

BMI is flawed science for lots of people....

For example: my dear friend is a competitive bodybuilder. He's 6' tall, and around 217lbs. His BMI is 29.8 which makes him overweight. However, his body fat is 9%. I've seen him at his *healthy* BMI at 185 lbs, and he's anorexic skinny.

A guy I used to train with got a call from some clerk at his doctor's office. She informed him that he was "at risk of obesity" due to his BMI. He's a triathlon athlete with bodyfat of like 12%. Definitely NOT overweight.