Is BMI really BS?

QueenBishOTUniverse

not really all bs IMHO, as a general guideline it makes sense to the majority of the population...People constanly use a few "outliers" (no offense to anyone I hope) as counter example...but seriouly...

But again, you don't know if you are one of the majority of the population for which it works

Also, I'm seeing a lot more than a few outliers on those graphs, in BOTH directions, and since fat is what we're actually concerned about when it comes to health, those graphs tell me that BMI pretty much sucks at predicting how fat I actually am.

Wonderob

not really all bs IMHO, as a general guideline it makes sense to the majority of the population...People constanly use a few "outliers" (no offense to anyone I hope) as counter example...but seriouly...

But again, you don't know if you are one of the majority of the population for which it works

Why do you want to argue about this? We are talking about if it's total BS, not if it's total BS to ME. right? So the answer is no, it's not total BS, and it's not total BS to me either.

We are discussing whether or not the BMI chart is anyway useful

The OP is on the edge of healhy/overweight - Is the BMI chart of any use whatsoever to her? Not in the slightest

I can't see a single benefit in looking at the chart - it's totally useless if you only go by the criteria that the BMI chart uses

It's like saying to you, "I weigh 150lbs, am I overweight?" How could you possibly know based on that limited knowledge

YoungIronG

i am obese according to my BMI

my pants size is 36

albayin

just like any theory out there, it's all down to how you feel about it. If you believe it's BS, then just don't follow it. Simple as that.

Wonderob

Also, I'm seeing a lot more than a few outliers on those graphs, in BOTH directions, and since fat is what we're actually concerned about when it comes to health, those graphs tell me that BMI pretty much sucks at predicting how fat I actually am.

Yeah I'll add some more from the National centre for weight and wellness

Conclusions based only on this number can be misleading, especially when it comes to the following:
How muscular you are: A few people have high BMIs but don't have much body fat. Their muscle tissue pushes up their weight. An example: "A football player or a body builder who is very muscular. Their BMI shows up pretty high, and yet their body fat is actually pretty low,"

Your activity level: Someone who is very inactive may have a BMI in the normal range and have lots of body fat, though they may not look out of shape. "They have very low levels of muscle and bone -- often elderly people, those in poor shape, sometimes those who are sick. Their BMI can look in the normal range, even though they have quite a lot of body fat in comparison to their lean body mass,"
"Ultimately, they have similar risks as people who carry lots of body fat and have a high BMI."

Your body type: Are you an apple shape or a pear shape? The location of your fat makes a difference to your health. Generally, it's the abdominal fat, or the "apple" shape, that's metabolically riskier. When fat settles around the waist instead of the hips, the chance of heart disease and type 2 diabetes goes up. Fat that accumulates on the hips and thighs, or the "pear" shape, isn't as potentially harmful.

Your age: The notion of an ideal BMI may shift with age. "People who are older probably should have a little more fat on them, [but] they shouldn't have a BMI of 30," Atkinson says. He points out that late in life, people who are "a little bit overweight" tend to have a better survival rate than leaner people. The reasons for that aren't totally clear, but it may have to do with having reserves to draw upon when fighting off an illness. It's hard to tell for sure, since many factors affect your health.

Your ethnicity: Major ethnic differences exist regarding BMI. For example, Asian-Americans tend to develop health risks, including the risk of diabetes, at significantly lower BMIs than whites. A healthy BMI for Asians ranges from 18.5 to 23.9, a full point lower than the standard range. More strikingly, Asians are considered obese at a BMI of 27 or higher compared, to the standard BMI obesity measure of 30 or higher.

csuhar

I can agree with this to some extent. The only problem is body shape. It doesn't take into account anything other than numbers.

What does body shape have to do with BMI or body weight?

Well, there's the issue that humans aren't diverse in terms of body structure with regards only to height. We also vary in regard to how wide and deep our skeletal structure is.

My brother, for example, is only an inch shorter than me, but can hide behind me because I have a broader build. That increased size from side-to-side is going to add weight. My brother's feet are somewhere like a US size 10.5. My feet are a US size 15. I don't know exactly what his head size is, but I do know he readily finds hats in his size while I have to find the biggest hats a company makes and even then they don't always fit on my size 8 cranium.

As a result, all those dimensions where I'm larger than my brother- height, breadth, foot size, head size, etc are increases in size that are also going to add weight, even if we actually have the same amount of fat on our bodies. But all the BMI sees is the difference between my brother being 6'1" and me being 6'2".

That's why the BMI is **GENERALLY** useful, but it's not really going to give you a detailed, personalized result you may want to work with.

SnicciFit

No, it's not BS. BMI is a generalization that will work for generally most people. It's become very common these days to attack BMI due to the outliers who have a higher than typical muscle mass, and thus for whom BMI is of little use. However the vast majority of people aren't rocking the amount of additional lean mass needed to skew the BMI radically.

The heart of the matter, for many, is that they hate that BMI tells them they're still too fat. A lot of people have come to loathe the old height/weight chart ranges and BMI because they point to the fact that we've, on the whole, lost perspective of just how small most people need to be in order to not be overweight. Especially here in the US we've become very, very skewed about appropriate weight and BMI.

As far as your own personal goals, are your health markers good? When looking in the mirror do you have excess fat that you're unhappy with? When you say you "dislike" your body, what exactly do you dislike? That there is still too much fat mass or are you talking about other parts that are unchangeable (naturally speaking)?

BMI knows nothing about how fat you are. Only what your height to weight ratio is. There is nothing in the BMI calculation that determines if you carry a lot of fat or not. Yes, in my opinion, it's mostly BS.

Wonderob

just like any theory out there, it's all down to how you feel about it. If you believe it's BS, then just don't follow it. Simple as that.

Eh? It WAS promoted by governments and advisers as being the way to judge whether of not you are healthy. That's pretty important!

Doctors and governments in the 1920s used to promote cigarettes as being good for your health.
Are you suggesting that people shouldn't challenge this, and instead just say "Oh well, if you didn't believe them you should just ignore this claim and call it BS?

QueenBishOTUniverse

just like any theory out there, it's all down to how you feel about it. If you believe it's BS, then just don't follow it. Simple as that.

Eh? It WAS promoted by governments and advisers as being the way to judge whether of not you are healthy. That's pretty important!

Doctors and governments in the 1920s used to promote cigarettes as being good for your health.
Are you suggesting that people shouldn't challenge this, and instead just say "Oh well, if you didn't believe them you should just ignore this claim and call it BS?

And there's the rub. I'm trained in science, I can look at those graphs and see that the actual predictive value of BMI for telling me if I'm too fat or not is practically nil. The average person doesn't have a clue about this, they go to a doctor's office or on to a site like WebMD, look at the chart and say oh, well according to this I'm healthy. Well no actually, the bmi chart can't tell you that AT ALL but most people won't investigate any further than that one basic step.

Akimajuktuq

I think the only people on the planet to whom you should listen regarding your weight loss goals are your doctor, and the person in your mirror, but that's just me.

Well, my doctor said I'm healthy but it's discouraging to see BMI doesn't exactly think so.

So a number determined by someone's idea of what's "normal" for "most" people is how you are going to measure whether you are healthy or not? Not by how you feel, or by how active you are, or by how strong you are, or by lack of illness? At least your doctor is reasonable (not all are and few have education in nutrition).

Why are you choosing to be discouraged? That doesn't seem useful in any way to me. But to each their own. Good luck.

SideSteel

Saying its completely useless is just as short sighted as saying that its the ultimate metric.

It's one tool and its important to recognize exactly what it tells you. And for what it tells you, and for its intended use, it is pretty good for the general population.

Wonderob

Saying its completely useless is just as short sighted as saying that its the ultimate metric.

It's one tool and its important to recognize exactly what it tells you. And for what it tells you, and for its intended use, it is pretty good for the general population.

And we are back to the general population argument

Am I in the general population? Is my wife?

So we both look at the BMI chart and find we're both on the verge of healthy/overweight

Tell me how it's pretty good for me or my wife based on what you know?

SideSteel

Saying its completely useless is just as short sighted as saying that its the ultimate metric.

It's one tool and its important to recognize exactly what it tells you. And for what it tells you, and for its intended use, it is pretty good for the general population.

And we are back to the general population argument

Am I in the general population? Is my wife?

So we both look at the BMI chart and find we're both on the verge of healthy/overweight

Tell me how it's pretty good for me or my wife based on what you know?

I'm not sure what your point is. There are athletic people, typically those who have years of resistance training experience, for whom the BMI scale may not be reasonable.

There are also those who are in denial about their level of fatness.

I cannot determine the answer to this in your specific example based on the information I currently have.

Do you believe that all calorie estimation calculators are completely useless because there are outliers?

stevencloser

I'm surprised no one posted this yet.

Hornsby

I'm surprised no one posted this yet.

Yea, but more people that are closer aligned to the obese guy use the ripped the guy as their excuse.

QueenBishOTUniverse

Saying its completely useless is just as short sighted as saying that its the ultimate metric.

It's one tool and its important to recognize exactly what it tells you. And for what it tells you, and for its intended use, it is pretty good for the general population.

And we are back to the general population argument

Am I in the general population? Is my wife?

So we both look at the BMI chart and find we're both on the verge of healthy/overweight

Tell me how it's pretty good for me or my wife based on what you know?

I'm not sure what your point is. There are athletic people, typically those who have years of resistance training experience, for whom the BMI scale may not be reasonable.

There are also those who are in denial about their level of fatness.

I cannot determine the answer to this in your specific example based on the information I currently have.

Do you believe that all calorie estimation calculators are completely useless because there are outliers?

I would classify myself as an outlier and I certainly don't have years of resistance training, months yes, years no. I might have been ok with saying "most people" but concerned about the effect it had on the mentality of the small number of outliers that BMI doesn't really work for.

But quite frankly I am shocked at how many outliers there were on that graph, if anything I would say that based on that data, BMI is actually skewing TOO LOW for most women. In other words, they're actually FATTER than they think they are, and that's an even worse problem from a health stand point then the issue of does it skew to far for those of us that have more LBM than average.

AlliSteff

It is definitely a tool, but really my BMI went from 25.7 to 25.3, but my body fat percentage dropped by almost 10% in the same time frame (8 months). I lost 13.25 lb of fat and gained 10.25 lb of lean muscle. But I only lost 3 lb on the scale.

So someone is going to tell me I am just a teeny bit healthier than I was before? Granted, I have never had a doctor say that to me ever....but it is an interesting look (when you are measuring things like inches and body fat percentage regularly) and utilizing other methods to track can help to analyze your 'health' in other ways

Fit_Chef_NE

Do you want a real answer or just want to delude yourself to feel better? The real answer is that unless you are an extreme bodybuilder, BMI is fairly accurate. My guess is, if it says you're overweight, you're overweight.

If you'd rather rely on how you feel instead of the truth, then no, you're not overweight and all doctors are full of it.


Or you could just be proud of how far you've come and realize you aren't done yet. Besides, if you think you can just stop dieting once you reach your goal, you'll be fat again in no time anyway. Best to just stick to the lower calories for life no?

Wonderob

I'm not sure what your point is. There are athletic people, typically those who have years of resistance training experience, for whom the BMI scale may not be reasonable.

There are also those who are in denial about their level of fatness.

I cannot determine the answer to this in your specific example based on the information I currently have.

Do you believe that all calorie estimation calculators are completely useless because there are outliers?

My point is that by 'General population', what do you mean? Is it me? My wife? You? How do we know?

If I heard that the calorie estimation calculators only worked for 'some' of the population; and that they could give massively inaccurate results in a fairly large number of cases; and that the results of the inaccuracies could have serious implications, AND I could have a pretty damned reasonable guess as to what the calculations were going to tell me just by looking, then yes, they would be useless too

stevencloser

I'm surprised no one posted this yet.

Yea, but more people that are closer aligned to the obese guy use the ripped the guy as their excuse.

True enough. But the longer you do strength training the less accurate bmi becomes for you. It's only good for basically sedentary people.