Is BMI really BS?

Iwishyouwell

Not everyone who claims to be an outlier on BMI is delusional about their weight. Yes, a lot of people use it as an excuse for why they are overweight, but there are plenty of people, including several who have posted to this thread and the OP, that classify as near/overweight according to BMI, that are perfectly healthy by EVERY other indicator. To imply that outliers only exist in cases of extreme athletes and body builders is simply not true.

Actually the OP of this thread proves out the BMI. She's at a healthy BMI.

A straw man was built at the top of this thread by a few of you who started equated "higher end of the BMI" to basically overweight. Several of you went on to say that you would look too skinny in the mid range of the BMI.

Except nobody said the OP, or anyone, had to shoot for the middle or low range of the BMI.

Almost everyone in this thread who is arguing against the merits of the BMI could stand to lose a few pounds and would fall right into the BMI "healthy" range.

That's what's hilarious here. So far there have been almost no true outliers. Just people who are already on the higher end of the "healthy" BMI range, or are just a bit above and, when leaned down, would fall right in line with the "healthy" BMI.

bennettinfinity

This is *exactly* why the BMI as applied to INDIVIDUALS is a crock!

At my current height (74 inches) and LBM (171 LBS) my 'healthy' BMI range allows for BF% of between -15.5% to 11.3%... that's right NEGATIVE 15.5% BF - not to mention that I would still be considered overweight at 11.4% BF... but my company also structures insurance contributions based on BMI - seems legit. :eyeroll:

I'd say viewing lean mass as a static figure when significantly overweight is a bigger problem than BMI.

Much like the BMI, you don't know anything about me or how overweight I might happen to be. Yes my LBM will not be static, but of the 54 LBS i've lost to date, fewer than 10 of those have been from LBM. So the point is that while I still have some excess BF, BMI would tell me I need to drastically cut LBM to achieve some magical BMI nirvana... and in my opinion *that* would be an unhealthy approach to weight loss.

Or I could just cut off a leg.

Iwishyouwell

Good work in here Iwishyouwell. I agree with everything you've said, and I'm a muscular BMI "overweight". It doesn't bother me at all, because I obviously fit the caveat that appears with almost every BMI calculator out there. I've put on muscle to get here. And the average person does not look like I do.

I can only imagine how frustrating it is for people like you, who put in the work to be an outlier, having so many just too-fat people pulling their cart up alongside you, using you as an example as to why the entire BMI chart is bull****.

Mr_Knight

The more weight I lost, the more I realized I wasn't the big-boned, strapping hulk of an outlier I thought I was.

Funny how that works...

SomeNights246

I wouldn't say it's pure BS. I think it is just a guideline. What is BS is that some people take it as the end all be all, when it isn't. Even doctors will often tell you it's just a guideline. Everyone is different. You have to consider muscle mass, hip size, thigh size, breast size, butt size, how the weight is distributed, etc.

I don't even know my BMI anymore. I used to, but when I stopped going by it, I found I could have more peace of mind. People stress over it too much. It is a good guideline for the average person. You will have the occasional person who will not look right within their 'healthy' BMI range, but they are the exception, not the rule.

My shape still is kind of 'big', but my BMI is within the healthy range. I feel healthy now, too. According to the BMI, I could still be 'healthy' if I lost ten more lbs. That's what I disagree with. Too often people forget there's a range of what can be considered 'healthy' for a reason.

Iwishyouwell

The more weight I lost, the more I realized I wasn't the big-boned, strapping hulk of an outlier I thought I was.

Funny how that works...

Ditto.

Funny how different you look when you start to get lower than your "big boned" weight.

Fat is incredibly visually deceptive. And if you're out of the obvious obese or very overweight range, it's quite possible to look "good enough", particularly if you live in one of the fatter nations, and come out thinking that you really don't have much fat left to lose.

Many people who are still clinically overweight might be shocked to discover that yes, you can afford to still lose 20-30 lbs and you won't look sickly, gaunt, or underweight.

Iwishyouwell

These are fun articles:
http://www.runnersworld.com/womens-running/bmis-of-champions-womens-edition
http://www.runnersworld.com/elite-runners/bmis-champions

My favorite part:

Normal Weight: 18.5-24.9
Most Olympic champions and nearly all of the runners fall into the normal weight category. The sprinter Usain Bolt is at the high end of the range. The hurdlers and jumpers are in the middle. The 5K and 10K champion, Mo Farah, is at the low end.

Most Olympic athletes are within the "normal weight" BMI category.

Yet here on MFP all the snowflakes, and their snowflake friends, are the outliers who are the ripped demi-gods who get miscategorized as "overweight".

You know, like LeBron James.

Mr_Knight

Most Olympic champions and nearly all of the runners fall into the normal weight category[/b]. The sprinter Usain Bolt is at the high end of the range. The hurdlers and jumpers are in the middle. The 5K and 10K champion, Mo Farah, is at the low end.

Usain Bolt is only 205 pounds at 6'3".

manicautumn

I think BMI has merit at the low end and the really high. It's sketchy at the transition point though. Definitely a good motivator though.

erickirb

Most Olympic champions and nearly all of the runners fall into the normal weight category[/b]. The sprinter Usain Bolt is at the high end of the range. The hurdlers and jumpers are in the middle. The 5K and 10K champion, Mo Farah, is at the low end.

Usain Bolt is only 205 pounds at 6'3".

Nope, 6'5" 207, http://usainbolt.com/bio/

QueenBishOTUniverse

I though you might find this useful.



The National Institutes of Heath did a study called: Accuracy of Body Mass Index to Diagnose Obesity In the US Adult Population

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877506/

I'm sorry, but to me, this data speaks for itself, the r-squared values are laughable, BMI has almost NO predictive value in establishing how fat you are, and there are a whole hell of a lot of supposedly non existent outliers, on ALL sides of the correlation line. It doesn't tell you how healthy you are, it doesn't tell you how fat you are, all it tells you is how your height and weight compare to everybody else, so what good is it?

Wonderob

That's what's hilarious here. So far there have been almost no true outliers. Just people who are already on the higher end of the "healthy" BMI range, or are just a bit above and, when leaned down, would fall right in line with the "healthy" BMI.

There seems to be an agenda here against those that are overweight on the BMI chart yet refuse to accept they are fat

Too many are saying that overweight people are looking for an excuse to stay fat -maybe so, and I would agree with you on that; however that's got little to do with BMI

You want a true 'outier'? look no further

I am not an athlete, not a bodybuilder, don't look like a running back or Christiano Ronaldo, would consider myself as pretty normal (ok I'm below average height but not freakishly I hope!)

I was:
165lbs
23% BF
BMI = 27.2
= Overweight (and looked and felt it)

Last year
160lbs
16% BF
BMI = 26.3
= Overweight according to BMI - didn't look it, didn't feel it, was told I wasn't overweight

I lost some weight, gained a little muscle - my BMI changed very little.

Mine was just a small transformation from being fat and having no muscle to being not fat and having a little muscle

The BMI charts said my transformation went from being overweight.... to being overweight

http://www.myfitnesspal.com/photos/view/18401123

1saturn

I think BMI has merit at the low end and the really high. It's sketchy at the transition point though. Definitely a good motivator though.

Yeah! That makes sense.

erickirb

I though you might find this useful.



The National Institutes of Heath did a study called: Accuracy of Body Mass Index to Diagnose Obesity In the US Adult Population

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877506/

I'm sorry, but to me, this data speaks for itself, the r-squared values are laughable, BMI has almost NO predictive value in establishing how fat you are, and there are a whole hell of a lot of supposedly non existent outliers, on ALL sides of the correlation line. It doesn't tell you how healthy you are, it doesn't tell you how fat you are, all it tells you is how your height and weight compare to everybody else, so what good is it?

I don't think it is as bad as you think. It would be nice to show 2 other trend lines above and below the average that are 2 standard deviations from the mean. I bet you would then see where the outliers are... the trend is there and can be noticed, but with a lot of variation, so the lines would be further from the mean, but it is still not that bad of an indicator for the majority of the population

stevencloser

I though you might find this useful.



The National Institutes of Heath did a study called: Accuracy of Body Mass Index to Diagnose Obesity In the US Adult Population

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877506/

I'm sorry, but to me, this data speaks for itself, the r-squared values are laughable, BMI has almost NO predictive value in establishing how fat you are, and there are a whole hell of a lot of supposedly non existent outliers, on ALL sides of the correlation line. It doesn't tell you how healthy you are, it doesn't tell you how fat you are, all it tells you is how your height and weight compare to everybody else, so what good is it?

I don't think it is as bad as you think. It would be nice to show 2 other trend lines above and below the average that are 2 standard deviations from the mean. I bet you would then see where the outliers are... the trend is there and can be noticed, but with a lot of variation, so the lines would be further from the mean, but it is still not that bad of an indicator for the majority of the population

There's still a difference of 20~% bodyfat between the higher and lower people at the exact same bmi.

Wonderob

I don't think it is as bad as you think. It would be nice to show 2 other trend lines above and below the average that are 2 standard deviations from the mean. I bet you would then see where the outliers are... the trend is there and can be noticed, but with a lot of variation, so the lines would be further from the mean, but it is still not that bad of an indicator for the majority of the population

That's what I keep hearing - The MAJORITY of the population. Or MOST people. Or NORMAL people

So how do you tell? Am I in the majority or not? Is my wife? Are you? If you don't know if the BMI chart is relevant to you then it's useless

Ben_the_builder

I am 5'10" and 240 lbs, my BMI is between 34 and 35 so I am obese. I am half way to the morbid obesity rating. My profile pic/ avatar pic are from about 2 months ago (I weighed 233 lbs in those) so as you can see in those photos I am not fat. BMI is complete garbage. It only factors a height to weight ratio. It does not take body composition into account.

Iwishyouwell

I was:
165lbs
23% BF
BMI = 27.2
= Overweight (and looked and felt it)

Last year
160lbs
16% BF
BMI = 26.3
= Overweight according to BMI - didn't look it, didn't feel it, was told I wasn't overweight

I lost some weight, gained a little muscle - my BMI changed very little.

Mine was just a small transformation from being fat and having no muscle to being not fat and having a little muscle

The BMI charts said my transformation went from being overweight.... to being overweight

http://www.myfitnesspal.com/photos/view/18401123

That's awesome. You are a short man who recomped by putting on a nice amount of muscle mass, and just barely creeping outside the BMI for your shorter height. Congratulations.

You, barely an outlier, have what to do with the general BMI? Most men at your height aren't going to look as ripped as you do at 160 lbs (assuming the after pic isn't wildly flexed).

The funny thing? You're at 16% body fat. Getting athletic lean would land you...right in the "healthy" BMI range. Again, you are just barely an outlier, yet you're the most vehement anti-BMI opponent in this thread.

Wonderob

That's awesome. You are a short man who recomped by putting on a nice amount of muscle mass, and just barely creeping outside the BMI for your shorter height. Congratulations.

You, barely an outlier, have what to do with the general BMI? Most men at your height aren't going to look as ripped as you do at 160 lbs (assuming the after pic isn't wildly flexed).

The funny thing? You're at 16% body fat. Getting athletic lean would land you...right in the "healthy" BMI range. Again, you are just barely an outlier, yet you're the most vehement anti-BMI opponent in this thread.

It doesn't matter what I am though - underweight, normal or overweight it wouldn't alter my view that the BMI chart adds nothing to what people already know. I didn't look at my BMI and realise that I was overweight - there were numerous indicators

Just as now I don't look at my BMI and wonder if I'm overweight - the signs are no longer there

Are there really that many overweight people that don't realise until they see it on a BMI chart?

Mr_Knight

My profile pic/ avatar pic are from about 2 months ago (I weighed 233 lbs in those) so as you can see in those photos I am not fat.

You're not fat.

You are, however, overweight.

Over the long run, that's not healthy, either.

stevencloser

You keep saying "if you push your bf% down you'd be right back in the normal weight" Well obviously they would. That's simple maths And if that isn't enough to get you to normal weight, cut some more fat until you are. But doing that is an exception in itself. The average man is at around 15% bf and not sub 10% or even 5% and a muscular person at this normal amount of bodyfat could easily fall into the overweight category where nonmuscular people with higher bf% are because of the way the bmi ranges were made.

Hornsby

That's awesome. You are a short man who recomped by putting on a nice amount of muscle mass, and just barely creeping outside the BMI for your shorter height. Congratulations.

You, barely an outlier, have what to do with the general BMI? Most men at your height aren't going to look as ripped as you do at 160 lbs (assuming the after pic isn't wildly flexed).

The funny thing? You're at 16% body fat. Getting athletic lean would land you...right in the "healthy" BMI range. Again, you are just barely an outlier, yet you're the most vehement anti-BMI opponent in this thread.

It doesn't matter what I am though - underweight, normal or overweight it wouldn't alter my view that the BMI chart adds nothing to what people already know. I didn't look at my BMI and realise that I was overweight - there were numerous indicators

Just as now I don't look at my BMI and wonder if I'm overweight - the signs are no longer there

Are there really that many overweight people that don't realise until they see it on a BMI chart?

Well, there has already been one in this thread.

jwdieter

See my post on page 5. 153 lbs at 12.2% BF BMI at 26.3%. My lean mass is 134.4 lbs. That would mean in order for me to fit in the BMI normal range I would have to be at 8% BF. I am a woman. I would consider that variance between the 2 to be a clear indication that for me "lose a few pounds and would fall right into the BMI "healthy" range" is irrelevant.

BTW I too have an insurance company that looks at BMI as a way to measure health factors for discounts. Stinks I miss out on that one parameter. Unfortunately I am not willing to lose muscle I have worked to gain to fit the BMI box.

If your measurements are accurate, you're ridiculously off the charts. Are you a professional bodybuilder?

Hornsby

I do not compete, no. I have several friends who do and have gleaned information from them as well as hours and hours of reasearch and trial and error on my own. I have consistently focused on developing muscle while shedding fat since August 2012.

Got any pics?

Wonderob

That's awesome. You are a short man who recomped by putting on a nice amount of muscle mass, and just barely creeping outside the BMI for your shorter height. Congratulations.

You, barely an outlier, have what to do with the general BMI? Most men at your height aren't going to look as ripped as you do at 160 lbs (assuming the after pic isn't wildly flexed).

The funny thing? You're at 16% body fat. Getting athletic lean would land you...right in the "healthy" BMI range. Again, you are just barely an outlier, yet you're the most vehement anti-BMI opponent in this thread.

It doesn't matter what I am though - underweight, normal or overweight it wouldn't alter my view that the BMI chart adds nothing to what people already know. I didn't look at my BMI and realise that I was overweight - there were numerous indicators

Just as now I don't look at my BMI and wonder if I'm overweight - the signs are no longer there

Are there really that many overweight people that don't realise until they see it on a BMI chart?

Well, there has already been one in this thread.

You're unlikely to look at a BMI calculator if you don't suspect that you are overweight. If you're borderline overweight then the BMI chart is of little value. If you're significantly overweight then most will already know

That person in question went on to say that they also looked at a number of other indicators too including BF to establish if they were overweight

jwdieter

I do not compete, no. I have several friends who do and have gleaned information from them as well as hours and hours of reasearch and trial and error on my own. I have consistently focused on developing muscle while shedding fat since August 2012.

Well, you've apparently managed to achieve a higher relative muscle mass than Iris Kyle (8x Ms Olympia), so that's.. something.

sodakat

The U.S. D.O.T (department of transportation) implemented new guidelines for CD (commercial drivers license) holders specifically aimed at over the road truckers. If our BMI is 35 or higher a sleep apnea test can be required and if OSA is diagnosed the use of a CPAP machine can be mandated along with periodic checkups and further testing. My doctor told me last month that she was going to be forced to cause big round guys to lose their jobs. Her words. She's been administering DOT physicals for 20 years and this is a huge change requiring all doctors be re certified and training ed to give the physical.

jwdieter

I don't share pictures. My response was in an effort to point out that there are people that are outside of the average BMI and losing a few pounds isn't a realsitic option. I am not any sort of professional and was making that point that for me the BMI chart is not accurate.

The problem with what you're saying is like me saying I'm a natural 5'10 270 with shredded lower glutes. You're claiming 10% lower body fat than any woman with similar BMI on the study quoted many times in this thread. It's simply not believable, so your point isn't particularly strong.

Iwishyouwell

That's awesome. You are a short man who recomped by putting on a nice amount of muscle mass, and just barely creeping outside the BMI for your shorter height. Congratulations.

You, barely an outlier, have what to do with the general BMI? Most men at your height aren't going to look as ripped as you do at 160 lbs (assuming the after pic isn't wildly flexed).

The funny thing? You're at 16% body fat. Getting athletic lean would land you...right in the "healthy" BMI range. Again, you are just barely an outlier, yet you're the most vehement anti-BMI opponent in this thread.

It doesn't matter what I am though - underweight, normal or overweight it wouldn't alter my view that the BMI chart adds nothing to what people already know. I didn't look at my BMI and realise that I was overweight - there were numerous indicators

Just as now I don't look at my BMI and wonder if I'm overweight - the signs are no longer there

Are there really that many overweight people that don't realise until they see it on a BMI chart?

I already told you. Me. Let me tell you what else the BMI taught me.

When I was in my 180s, looking good in clothes, but with a ton of fat still left on my trunk, looking at charts helped me realize that I wasn't really "big boned", and the weight ranges given were dead on for me if I wanted to be leaner.

The weight I had left was flabby and deflated looking. Many people would call it "loose skin". Deciding to continue cutting down lower into the previously, seemingly unrealistic ranges in the BMI charts actually taught me a very valuable lesson about excess/loose skin. A lot of the times it's just fat that can still be lost. If I hadn't paid attention to that, and continued to consider myself a big boned outlier who couldn't, or shouldn't, really get below my upper 180s, I'd have been one of these many still too-fat people walking around screaming about how much "loose skin" they still have.

The BMI charts were a huge eye opener to me about proper weight for myself, and many people. Realizing that the men of my dad and granddad's generation were, in general, well within those ranges back before the obesity crisis helped give me a lot of perspective.

bennettinfinity

I though you might find this useful.



The National Institutes of Heath did a study called: Accuracy of Body Mass Index to Diagnose Obesity In the US Adult Population

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2877506/

I'm sorry, but to me, this data speaks for itself, the r-squared values are laughable, BMI has almost NO predictive value in establishing how fat you are, and there are a whole hell of a lot of supposedly non existent outliers, on ALL sides of the correlation line. It doesn't tell you how healthy you are, it doesn't tell you how fat you are, all it tells you is how your height and weight compare to everybody else, so what good is it?

I don't think it is as bad as you think. It would be nice to show 2 other trend lines above and below the average that are 2 standard deviations from the mean. I bet you would then see where the outliers are... the trend is there and can be noticed, but with a lot of variation, so the lines would be further from the mean, but it is still not that bad of an indicator for the majority of the population

That's not how scatter plots work - the r-squared value indicates the data's predictive power. An r-square of 0.7 is considered a weak correlation, and only a fool would attempt to make predictions with an r-square below a 0.5. At best the plots show that NEWSFLASH! weight is correlated with height... really? Tall people generally weigh more than short people? Who'da thunk it?