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Is every single body in the world intended to be within the so-called healthy BMI range?
Replies
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Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing. In fact, from the authors' own conclusionsParadoxically, our study also suggests that the BMI markedly underestimated adiposity in young men (aged 20–29 years). It seems likely that for this group, body fat contributes more, and lean tissue less, to body weight than in other groups. While the reasons for this remain unclear, we might speculate that the fat-to-lean tissue mass ratio is disproportionately high as a result of unhealthy lifestyle choices including sedentary behaviour and poor nutrition. Differences in body composition might also be related to an increasing prevalence of growth hormone deficiency with increasing age, resulting in loss of lean tissue and increases in body fat [17]. These findings have public health implications, as the prevalence of adult obesity as described by the BMI, may be underestimated at a population level, particularly among men.
Both the BMI and %BF identify weight or fat mass relative to the whole body, but this has been conceptualized differently for the two indices. The BMI expresses body weight (kg) relative to stature (height, m2) and it should be noted that adjustment for height in this index is suboptimal [18]. The second order polynomial relationship between BMI and %BF [5] is partly explained by the relative relationship of body fat mass to total body weight; increments in body fat mass result in diminishing increments in %BF. Furthermore, accumulation of body fat in healthy bodies is generally accompanied by a compensatory response from the musculoskeletal system, acting through mechanoreceptors in muscle and bone, as it adapts to better cope with the increasing mechanical load [19]. Adipokines also act as regulatory messengers between adipocytes in fat deposits, muscle [20] and bone [21, 22]. However, with excessive accumulation of body fat, the increased loading could exceed compensatory musculoskeletal responses thereby altering the proportions of fat, lean and bone issue. As a consequence, increases in BMI could reflect increased weight-for-height yet mask changes in body composition. Considering the obesity epidemic, a more accurate indicator of body fatness is required to better assess obesity-related health risks.
1. In young males (the group most likely to think they're "too muscular for BMI" they found that BMI significantly under estimated fat. That BMI was in fact too generous.
2. They further explain that one of the reasons obese people are only "overweight" by BF% is precisely because a lifetime of obesity triggers more bone and muscle to grow. A point I remember having made REPEATEDLY here in this thread and others.
Again, for the n-th time, the paper doesn't in any way, in any part, in the data, the discussion, or the conclusions, make any statements about "normal weight" people. It is specifically analyzing and discussing OBESE people. And because the study found that 3 standard deviations of individuals fit within 1 category of their BMI predicted category, we can thus infer that the overwhelming, by an order of magnitude, number of people that fall in the OBESE category in EITHER MEASURE, are NOT healthy weight UNDER EITHER MEASURE.
Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.1 -
Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing. In fact, from the authors' own conclusionsParadoxically, our study also suggests that the BMI markedly underestimated adiposity in young men (aged 20–29 years). It seems likely that for this group, body fat contributes more, and lean tissue less, to body weight than in other groups. While the reasons for this remain unclear, we might speculate that the fat-to-lean tissue mass ratio is disproportionately high as a result of unhealthy lifestyle choices including sedentary behaviour and poor nutrition. Differences in body composition might also be related to an increasing prevalence of growth hormone deficiency with increasing age, resulting in loss of lean tissue and increases in body fat [17]. These findings have public health implications, as the prevalence of adult obesity as described by the BMI, may be underestimated at a population level, particularly among men.
Both the BMI and %BF identify weight or fat mass relative to the whole body, but this has been conceptualized differently for the two indices. The BMI expresses body weight (kg) relative to stature (height, m2) and it should be noted that adjustment for height in this index is suboptimal [18]. The second order polynomial relationship between BMI and %BF [5] is partly explained by the relative relationship of body fat mass to total body weight; increments in body fat mass result in diminishing increments in %BF. Furthermore, accumulation of body fat in healthy bodies is generally accompanied by a compensatory response from the musculoskeletal system, acting through mechanoreceptors in muscle and bone, as it adapts to better cope with the increasing mechanical load [19]. Adipokines also act as regulatory messengers between adipocytes in fat deposits, muscle [20] and bone [21, 22]. However, with excessive accumulation of body fat, the increased loading could exceed compensatory musculoskeletal responses thereby altering the proportions of fat, lean and bone issue. As a consequence, increases in BMI could reflect increased weight-for-height yet mask changes in body composition. Considering the obesity epidemic, a more accurate indicator of body fatness is required to better assess obesity-related health risks.
1. In young males (the group most likely to think they're "too muscular for BMI" they found that BMI significantly under estimated fat. That BMI was in fact too generous.
2. They further explain that one of the reasons obese people are only "overweight" by BF% is precisely because a lifetime of obesity triggers more bone and muscle to grow. A point I remember having made REPEATEDLY here in this thread and others.
Again, for the n-th time, the paper doesn't in any way, in any part, in the data, the discussion, or the conclusions, make any statements about "normal weight" people. It is specifically analyzing and discussing OBESE people. And because the study found that 3 standard deviations of individuals fit within 1 category of their BMI predicted category, we can thus infer that the overwhelming, by an order of magnitude, number of people that fall in the OBESE category in EITHER MEASURE, are NOT healthy weight UNDER EITHER MEASURE.
Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
The information you're claiming isn't there is in chart 4. As I said before I don't have the time to wrangle the numbers.
But your persistent assertion that the data isn't there is incorrect.
As you said.
Read the *KITTEN* paper. don't just skim it.1 -
Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing.
I'm the one who posted it originally. I did, because I was surprised that the number misidentified as obese when they were not was so high, particularly for women. I was already aware that many were misidentified as not obese or overweight when they were, and have said that.
It was not posted to show BMI was "too mean" to lean people; that's your imagination.
As I read stanman's later citation of it, it was in response to your claim that no one could show that a meaningful number of people were misidentified, or misidentified as obese when they are not, and it does show that. It shows that BMI and BF% do not always line up (often do not) and in some non insignificant percentage BMI indicates that they are in a higher fat category than BF% would say. You were (as I read you) denying this.
I quoted already the part about people in many cases being fatter than BMI says too. This gotcha thing is totally fantasized on your part.Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
As stated before, it shows that BMI has limits in determining whether someone is overweight or obese by BF%, that other measures may be more helpful. Which is all anyone has claimed.
And no, it absolutely does not show that it is a bad tool for predicting extreme obesity (or only extreme obesity). 25% of women and over 33% of men were in the wrong category. We don't know the precise breakdown (without someone getting it from the tables), but it looks like it's roughly half (slightly less) of the miscategorized that BMI makes fatter than reality and half that it makes less fat (slightly more than half).
Why is it so important to you to insist that BMI works perfectly when the evidence is that it's an okay starting tool and good for population measures but not a perfect proxy for BF% for many?1 -
stanmann571 wrote: »Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing. In fact, from the authors' own conclusionsParadoxically, our study also suggests that the BMI markedly underestimated adiposity in young men (aged 20–29 years). It seems likely that for this group, body fat contributes more, and lean tissue less, to body weight than in other groups. While the reasons for this remain unclear, we might speculate that the fat-to-lean tissue mass ratio is disproportionately high as a result of unhealthy lifestyle choices including sedentary behaviour and poor nutrition. Differences in body composition might also be related to an increasing prevalence of growth hormone deficiency with increasing age, resulting in loss of lean tissue and increases in body fat [17]. These findings have public health implications, as the prevalence of adult obesity as described by the BMI, may be underestimated at a population level, particularly among men.
Both the BMI and %BF identify weight or fat mass relative to the whole body, but this has been conceptualized differently for the two indices. The BMI expresses body weight (kg) relative to stature (height, m2) and it should be noted that adjustment for height in this index is suboptimal [18]. The second order polynomial relationship between BMI and %BF [5] is partly explained by the relative relationship of body fat mass to total body weight; increments in body fat mass result in diminishing increments in %BF. Furthermore, accumulation of body fat in healthy bodies is generally accompanied by a compensatory response from the musculoskeletal system, acting through mechanoreceptors in muscle and bone, as it adapts to better cope with the increasing mechanical load [19]. Adipokines also act as regulatory messengers between adipocytes in fat deposits, muscle [20] and bone [21, 22]. However, with excessive accumulation of body fat, the increased loading could exceed compensatory musculoskeletal responses thereby altering the proportions of fat, lean and bone issue. As a consequence, increases in BMI could reflect increased weight-for-height yet mask changes in body composition. Considering the obesity epidemic, a more accurate indicator of body fatness is required to better assess obesity-related health risks.
1. In young males (the group most likely to think they're "too muscular for BMI" they found that BMI significantly under estimated fat. That BMI was in fact too generous.
2. They further explain that one of the reasons obese people are only "overweight" by BF% is precisely because a lifetime of obesity triggers more bone and muscle to grow. A point I remember having made REPEATEDLY here in this thread and others.
Again, for the n-th time, the paper doesn't in any way, in any part, in the data, the discussion, or the conclusions, make any statements about "normal weight" people. It is specifically analyzing and discussing OBESE people. And because the study found that 3 standard deviations of individuals fit within 1 category of their BMI predicted category, we can thus infer that the overwhelming, by an order of magnitude, number of people that fall in the OBESE category in EITHER MEASURE, are NOT healthy weight UNDER EITHER MEASURE.
Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
The information you're claiming isn't there is in chart 4. As I said before I don't have the time to wrangle the numbers.
But your persistent assertion that the data isn't there is incorrect.
As you said.
Read the *KITTEN* paper. don't just skim it.
nope. it does not.
It shows the number of people in non-ideal weight categories under both methods. It says absolutely nothing about which of those people were miscategorized. It only shows the differences in how many people are in each method, it doesn't show which direction the miscategorized people fell.
It also doesn't include the number in "Ideal weight" under either category, although you could calculate this category by subtracting the other categories.
How often do you read academic papers?2 -
because I have nothing better to do apparently. I went ahead and calculated the percent of people in "ideal weight" under each category more men.
Please notice that for most age groups far FEWER people are categorized as "ideal weight" under BF% than under BMI, meaning BMI is too generous. Which is what the paper argued.
1 -
stanmann571 wrote: »Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing. In fact, from the authors' own conclusionsParadoxically, our study also suggests that the BMI markedly underestimated adiposity in young men (aged 20–29 years). It seems likely that for this group, body fat contributes more, and lean tissue less, to body weight than in other groups. While the reasons for this remain unclear, we might speculate that the fat-to-lean tissue mass ratio is disproportionately high as a result of unhealthy lifestyle choices including sedentary behaviour and poor nutrition. Differences in body composition might also be related to an increasing prevalence of growth hormone deficiency with increasing age, resulting in loss of lean tissue and increases in body fat [17]. These findings have public health implications, as the prevalence of adult obesity as described by the BMI, may be underestimated at a population level, particularly among men.
Both the BMI and %BF identify weight or fat mass relative to the whole body, but this has been conceptualized differently for the two indices. The BMI expresses body weight (kg) relative to stature (height, m2) and it should be noted that adjustment for height in this index is suboptimal [18]. The second order polynomial relationship between BMI and %BF [5] is partly explained by the relative relationship of body fat mass to total body weight; increments in body fat mass result in diminishing increments in %BF. Furthermore, accumulation of body fat in healthy bodies is generally accompanied by a compensatory response from the musculoskeletal system, acting through mechanoreceptors in muscle and bone, as it adapts to better cope with the increasing mechanical load [19]. Adipokines also act as regulatory messengers between adipocytes in fat deposits, muscle [20] and bone [21, 22]. However, with excessive accumulation of body fat, the increased loading could exceed compensatory musculoskeletal responses thereby altering the proportions of fat, lean and bone issue. As a consequence, increases in BMI could reflect increased weight-for-height yet mask changes in body composition. Considering the obesity epidemic, a more accurate indicator of body fatness is required to better assess obesity-related health risks.
1. In young males (the group most likely to think they're "too muscular for BMI" they found that BMI significantly under estimated fat. That BMI was in fact too generous.
2. They further explain that one of the reasons obese people are only "overweight" by BF% is precisely because a lifetime of obesity triggers more bone and muscle to grow. A point I remember having made REPEATEDLY here in this thread and others.
Again, for the n-th time, the paper doesn't in any way, in any part, in the data, the discussion, or the conclusions, make any statements about "normal weight" people. It is specifically analyzing and discussing OBESE people. And because the study found that 3 standard deviations of individuals fit within 1 category of their BMI predicted category, we can thus infer that the overwhelming, by an order of magnitude, number of people that fall in the OBESE category in EITHER MEASURE, are NOT healthy weight UNDER EITHER MEASURE.
Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
The information you're claiming isn't there is in chart 4. As I said before I don't have the time to wrangle the numbers.
But your persistent assertion that the data isn't there is incorrect.
As you said.
Read the *KITTEN* paper. don't just skim it.
nope. it does not.
It shows the number of people in non-ideal weight categories under both methods. It says absolutely nothing about which of those people were miscategorized. It only shows the differences in how many people are in each method, it doesn't show which direction the miscategorized people fell.
It also doesn't include the number in "Ideal weight" under either category, although you could calculate this category by subtracting the other categories.
How often do you read academic papers?
It's ok, most people aren't very good at applied math and statistics.
Like I said above, It can be done, I just don't have the time.3 -
lemurcat12 wrote: »Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing.
I'm the one who posted it originally. I did, because I was surprised that the number misidentified as obese when they were not was so high, particularly for women. I was already aware that many were misidentified as not obese or overweight when they were, and have said that.
It was not posted to show BMI was "too mean" to lean people; that's your imagination.
As I read stanman's later citation of it, it was in response to your claim that no one could show that a meaningful number of people were misidentified, or misidentified as obese when they are not, and it does show that. It shows that BMI and BF% do not always line up (often do not) and in some non insignificant percentage BMI indicates that they are in a higher fat category than BF% would say. You were (as I read you) denying this.
I quoted already the part about people in many cases being fatter than BMI says too. This gotcha thing is totally fantasized on your part.Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
As stated before, it shows that BMI has limits in determining whether someone is overweight or obese by BF%, that other measures may be more helpful. Which is all anyone has claimed.
And no, it absolutely does not show that it is a bad tool for predicting extreme obesity (or only extreme obesity). 25% of women and over 33% of men were in the wrong category. We don't know the precise breakdown (without someone getting it from the tables), but it looks like it's roughly half (slightly less) of the miscategorized that BMI makes fatter than reality and half that it makes less fat (slightly more than half).
Why is it so important to you to insist that BMI works perfectly when the evidence is that it's an okay starting tool and good for population measures but not a perfect proxy for BF% for many?
for the n+1-th time.
miscategorizing "overweight" vs "obese" is STILL NOT A HEALTHY WEIGHT.
Still
not
healthy
weight
The claim was made that more than 20% of people think they're not healthy weight, when they are, or visa versa.
The data in THIS PAPER does not back up that hypothesis. It doesn't come close. It only establishes that >20% of fat people are either more or less fat under one tool or the other. It does present any data or conclusions about what % of fat people aren't actually fat, or what percentage of not fat people are actually fat.
stanman was wrong to post it as evidence to respond to my comment, because it contains NO SUCH EVIDENCE3 -
f-it, heres for men and women, the whole table 4, with Ideal Weight percentages calculated.
BMI is more forgiving than BF% for both men and women for the majority of age groups
2 -
lemurcat12 wrote: »Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing.
I'm the one who posted it originally. I did, because I was surprised that the number misidentified as obese when they were not was so high, particularly for women. I was already aware that many were misidentified as not obese or overweight when they were, and have said that.
It was not posted to show BMI was "too mean" to lean people; that's your imagination.
As I read stanman's later citation of it, it was in response to your claim that no one could show that a meaningful number of people were misidentified, or misidentified as obese when they are not, and it does show that. It shows that BMI and BF% do not always line up (often do not) and in some non insignificant percentage BMI indicates that they are in a higher fat category than BF% would say. You were (as I read you) denying this.
I quoted already the part about people in many cases being fatter than BMI says too. This gotcha thing is totally fantasized on your part.Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
As stated before, it shows that BMI has limits in determining whether someone is overweight or obese by BF%, that other measures may be more helpful. Which is all anyone has claimed.
And no, it absolutely does not show that it is a bad tool for predicting extreme obesity (or only extreme obesity). 25% of women and over 33% of men were in the wrong category. We don't know the precise breakdown (without someone getting it from the tables), but it looks like it's roughly half (slightly less) of the miscategorized that BMI makes fatter than reality and half that it makes less fat (slightly more than half).
Why is it so important to you to insist that BMI works perfectly when the evidence is that it's an okay starting tool and good for population measures but not a perfect proxy for BF% for many?
for the n+1-th time.
miscategorizing "overweight" vs "obese" is STILL NOT A HEALTHY WEIGHT.
Yes, everyone knows that. Again, 75% of women and less than 66% of men, of all categories, were in the wrong category. Almost all were just one off. That means there are people classified as overweight who are not, by BF%. That's what you (oddly) keep saying is not true.
BMI is a fine measure for most people and for populations, but for an individual it can be wrong, and there are better measures. Period.0 -
lemurcat12 wrote: »lemurcat12 wrote: »Let's tie a bow on this. The paper being used to attack BMI as being too "mean" to lean people, shows no such thing.
I'm the one who posted it originally. I did, because I was surprised that the number misidentified as obese when they were not was so high, particularly for women. I was already aware that many were misidentified as not obese or overweight when they were, and have said that.
It was not posted to show BMI was "too mean" to lean people; that's your imagination.
As I read stanman's later citation of it, it was in response to your claim that no one could show that a meaningful number of people were misidentified, or misidentified as obese when they are not, and it does show that. It shows that BMI and BF% do not always line up (often do not) and in some non insignificant percentage BMI indicates that they are in a higher fat category than BF% would say. You were (as I read you) denying this.
I quoted already the part about people in many cases being fatter than BMI says too. This gotcha thing is totally fantasized on your part.Read the damn paper people. Don't just skim it. This paper does not help the case that BMI is a bad tool for predicting someone's ideal weight, only that it is a bad tool for predicting extreme obesity, and that's because it doesn't consider enough people to be fat.
As stated before, it shows that BMI has limits in determining whether someone is overweight or obese by BF%, that other measures may be more helpful. Which is all anyone has claimed.
And no, it absolutely does not show that it is a bad tool for predicting extreme obesity (or only extreme obesity). 25% of women and over 33% of men were in the wrong category. We don't know the precise breakdown (without someone getting it from the tables), but it looks like it's roughly half (slightly less) of the miscategorized that BMI makes fatter than reality and half that it makes less fat (slightly more than half).
Why is it so important to you to insist that BMI works perfectly when the evidence is that it's an okay starting tool and good for population measures but not a perfect proxy for BF% for many?
for the n+1-th time.
miscategorizing "overweight" vs "obese" is STILL NOT A HEALTHY WEIGHT.
Yes, everyone knows that. Again, 75% of women and less than 66% of men, of all categories, were in the wrong category. Almost all were just one off. That means there are people classified as overweight who are not, by BF%. That's what you (oddly) keep saying is not true.
BMI is a fine measure for most people and for populations, but for an individual it can be wrong, and there are better measures. Period.
I'm not saying this is not true, it is obviously true. What I am pointing out is that
1. the paper does not contain the relevant data to know how many people meet this criteria
2. given that the number of ideal weight people falls, in some cases considerably, when moving from BMI to BF% it is quite reasonable to assume that the number of overweight people who are ideal weight under BF% is likely quite low, and almost certainly far less than 20%.
The paper is arguing, quite effectively, the BMI is an ineffective tool because it is most likely to UNDERESTIMATE how fat somebody it.
Meaning if the average person is trying to predict an "ideal weight" then BMI might actually be too generous, and they may need to aim lower than the upper bound of "ideal weight" for their height.
Keeping that in mind. BMI "ideal weight" is overly broad, which, mathematically, means an even LARGER portion of the population should be able to fit within it's "normal weight" category, and some of those will STILL be overfat.
So you're right. there ARE better measures, because BMI isn't strict enough.2 -
f-it, heres for men and women, the whole table 4, with Ideal Weight percentages calculated.
BMI is more forgiving than BF% for both men and women for the majority of age groups
I wonder if the fact that the only age groups for which BF% seems to be more permissive than BMI for both genders is "middle age" (40-70) contributes to why so many people here in particular think BMI shouldn't apply. An interesting observation to be sure.2 -
Hopefully my parting thought in this thread unless somebody drags me back in with some nonsense.
This paper addresses something that isn't talked about enough, and it often used inadvertently as an excuse.Furthermore, accumulation of body fat in healthy bodies is generally accompanied by a compensatory response from the musculoskeletal system, acting through mechanoreceptors in muscle and bone, as it adapts to better cope with the increasing mechanical load [19]. Adipokines also act as regulatory messengers between adipocytes in fat deposits, muscle [20] and bone [21, 22]. However, with excessive accumulation of body fat, the increased loading could exceed compensatory musculoskeletal responses thereby altering the proportions of fat, lean and bone issue. As a consequence, increases in BMI could reflect increased weight-for-height yet mask changes in body composition. Considering the obesity epidemic, a more accurate indicator of body fatness is required to better assess obesity-related health risks.
Somebody who is obese, particularly somebody who's been obese for a significant amount of time, will have a much higher LBM than they would if they were thin. This may lead them to believe that they don't "fit the BMI model" because the have too much muscle and bone. But this would be false. If they were to lose the fat, they would also very likely loose a significant amount of that additional muscle, and even some of the bone mass eventually. Pulling them back into the normal BMI range. If however they engage in rigourous weight training in order to keep that muscle mass, thus keeping them above the normal BMI range at a healthy BF%, they would be no different than a strength athlete that is a BMI outlier because they train for muscle mass. Additional work, above and beyond what is normal, was put in with the specific goal of maximizing muscle mass.
So thank you for posting this paper, as I think it provides a good deal of evidence to support the idea that under normal circumstances every body (in a statistical sense) should be able to fit into the normal weight BMI range, baring exceptions for disease, injury, or exceptional effort to build or reduce muscle mass outside the normal range.1 -
I'm not saying this is not true, it is obviously true.
Okay, good. I had understood you as claiming it was not, or so rarely as to be irrelevant.
That's really the only point I am interested in.What I am pointing out is that
1. the paper does not contain the relevant data to know how many people meet this criteria
I think that's probably true, although I have not tried to go through the tables sufficiently to know for sure. What I have found, in looking at a variety of such papers, is that researchers seem much more interested in how useful BMI is in identifying who is obese, probably because for health purposes that is what really matters.
However, what we do know is that 75% of women and under 67% of men are in the right categories, and how those categories break down for the obese -- substantially more people are obese by BF% in the younger categories than by BMI, but for women it's something like 17% categorized obese by BMI who are really overweight vs. 19% the other way around, and for men 30-something vs. 40-something. I think the numbers suggest that's a likely pattern for "ideal weight"/overweight too, which would indeed mean that a substantial number were miscategorized in both ways. But I have not claimed the study was definitive on this specific point, as that's neither why I posted it nor my (later) problem with what you seemed to be saying.
Again, I posted it because although I had known BF% showed that SOME men were miscategorized as obese who were not and some of both sexes were miscategorized as not obese who were, I was surprised the numbers were as high as they were, especially in the first category.3. given that the number of ideal weight people falls, in some cases considerably, when moving from BMI to BF% it is quite reasonable to assume that the number of overweight people who are ideal weight under BF% is likely quite low, and almost certainly far less than 20%.
No, it's not. Again, the obese percentage falls too, when moving from BF% to BMI, and yet we know that more than 20% of men are miscategorized both ways, and approximately 20% (a bit less) of women.The paper is arguing, quite effectively, the BMI is an ineffective tool because it is most likely to UNDERESTIMATE how fat somebody it.
Yes, that it part of it, but the bigger issue is it does both.
And again, everyone knows there are issues in both directions, I and others said this way, way, way upthread and I made that clear when posting the study.0 -
Hopefully my parting thought in this thread unless somebody drags me back in with some nonsense.
This paper addresses something that isn't talked about enough, and it often used inadvertently as an excuse.Furthermore, accumulation of body fat in healthy bodies is generally accompanied by a compensatory response from the musculoskeletal system, acting through mechanoreceptors in muscle and bone, as it adapts to better cope with the increasing mechanical load [19]. Adipokines also act as regulatory messengers between adipocytes in fat deposits, muscle [20] and bone [21, 22]. However, with excessive accumulation of body fat, the increased loading could exceed compensatory musculoskeletal responses thereby altering the proportions of fat, lean and bone issue. As a consequence, increases in BMI could reflect increased weight-for-height yet mask changes in body composition. Considering the obesity epidemic, a more accurate indicator of body fatness is required to better assess obesity-related health risks.
Somebody who is obese, particularly somebody who's been obese for a significant amount of time, will have a much higher LBM than they would if they were thin. This may lead them to believe that they don't "fit the BMI model" because the have too much muscle and bone. But this would be false. If they were to lose the fat, they would also very likely loose a significant amount of that additional muscle, and even some of the bone mass eventually. Pulling them back into the normal BMI range. If however they engage in rigourous weight training in order to keep that muscle mass, thus keeping them above the normal BMI range at a healthy BF%, they would be no different than a strength athlete that is a BMI outlier because they train for muscle mass. Additional work, above and beyond what is normal, was put in with the specific goal of maximizing muscle mass.
So thank you for posting this paper, as I think it provides a good deal of evidence to support the idea that under normal circumstances every body (in a statistical sense) should be able to fit into the normal weight BMI range, baring exceptions for disease, injury, or exceptional effort to build or reduce muscle mass outside the normal range.
(1) I'm finding it very rude and disingenuous that you keep trying to suggest that I did not realize the study said that there were misclassifications both ways. This is exactly what I said when posting the study:
"Here's one good comparison of BF% and BMI (given that the purpose of BMI is to act as a proxy for BF%): https://bmcobes.biomedcentral.com/articles/10.1186/2052-9538-1-9
Key findings (note, this is for white people in Australia, there are likely race-based differences):
*17.3% of women and 31.6% of men identified as obese according to BMI were not, based on BF%.
*19.9% of women and 46.1% of men who were NOT obese by BMI actually were by BF%
*BMI particularly underestimates adiposity in elderly men (aged 70 years and older), but also in young men (aged 20–29 years).
That's different from another such study I recall seeing in the past, where it was much more likely to mischaracterize women as not obese when they were than obese when they were not. There was more mischaracterization for the overweight category in that one (this one focused on obesity measures only)."
(2) I think you are correct on the limited (but irrelevant) point that most everyone COULD fit into a healthy BMI range. However, that does not mean that it's HEALTHIER to do so or that everyone SHOULD. It's clear there's a significant number of people who can be classified as overweight due in part to more than average muscle mass while being lean. Leanness is what matters (I currently believe, although if you think that's wrong, post something). If I were 20% BF (which is fine, quite lean even, for a woman) and 145 lb (overweight BMI) and 116 lean mass, I'd be totally fine and healthy. That's generally unlikely for me, but not impossible for someone of my size. It would take work.
If someone is both extra muscle-y due to building muscle during years of being overly heavy AND manages to lose the fat without losing all of the excess lean mass, due to protein + progressive weight training + good genes, that's probably a good thing, not a bad one.
I had a DEXA because I was curious about muscle mass, but also because I was curious about bone density. My bone density is great for my age. It's quite possible that's in part because I was overweight for a time (not saying it makes a difference to my appropriate BMI range), but that it was caused by being fat doesn't make it bad. Same with excess muscle mass.3 -
lemurcat12 wrote: »I'm not saying this is not true, it is obviously true.
Okay, good. I had understood you as claiming it was not, or so rarely as to be irrelevant.
That's really the only point I am interested in.What I am pointing out is that
1. the paper does not contain the relevant data to know how many people meet this criteria
I think that's probably true, although I have not tried to go through the tables sufficiently to know for sure. What I have found, in looking at a variety of such papers, is that researchers seem much more interested in how useful BMI is in identifying who is obese, probably because for health purposes that is what really matters.
However, what we do know is that 75% of women and under 67% of men are in the right categories, and how those categories break down for the obese -- substantially more people are obese by BF% in the younger categories than by BMI, but for women it's something like 17% categorized obese by BMI who are really overweight vs. 19% the other way around, and for men 30-something vs. 40-something. I think the numbers suggest that's a likely pattern for "ideal weight"/overweight too, which would indeed mean that a substantial number were miscategorized in both ways. But I have not claimed the study was definitive on this specific point, as that's neither why I posted it nor my (later) problem with what you seemed to be saying.
Again, I posted it because although I had known BF% showed that SOME men were miscategorized as obese who were not and some of both sexes were miscategorized as not obese who were, I was surprised the numbers were as high as they were, especially in the first category.3. given that the number of ideal weight people falls, in some cases considerably, when moving from BMI to BF% it is quite reasonable to assume that the number of overweight people who are ideal weight under BF% is likely quite low, and almost certainly far less than 20%.
No, it's not. Again, the obese percentage falls too, when moving from BF% to BMI, and yet we know that more than 20% of men are miscategorized both ways, and approximately 20% (a bit less) of women.The paper is arguing, quite effectively, the BMI is an ineffective tool because it is most likely to UNDERESTIMATE how fat somebody it.
Yes, that it part of it, but the bigger issue is it does both.
And again, everyone knows there are issues in both directions, I and others said this way, way, way upthread and I made that clear when posting the study.
Yes. Obese does fall. However, "overweight" increases by a greater amount that "Obese" falls. This leads to the conclusion that a greater number of both overweight and ideal weight people by BMI are in fact "overweight" by BF%.
There is nothing here to suggest that the ideal weight/overweight boundary is as erroneous or equally porous as the overweight/obese boundary. There is nothing in this study that would preclude that either.
As I have pointed out repeatedly, the data that stanman claimed was here when he replied to me and started this debate, simply does not exist in this study.
The study only contains data on the error in the overweight/obese boundary, as in public health research this is the only one that particularly matters.
Any assumptions you make about the healthy/overweight boundary is entirely and completely supposition, not based on any of the data in this report, at all.
The closest we can get is look at the % incorrect at the overweight/obese boundary and compare it to the overall incorrect ratio. Both of which are known. But as we can see, the percentage miscategorized at that boundary is higher than the miscategorized percentage for the whole population, meaning they make up a disproportionate number of all those miscategorized. For women the percentage is closer. The population suggests that 73.9% of women are correctly categorized, but only 62.8% of overweight or obese women are.
For men it's enormous though. The population would suggest that 62.6% of men are correctly categorized, but among overweight and obese men only 22.3% are. Meaning that nearly ALL of the miscategorized men are at the overweight/obese boundary.
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Numbers confirmed, actually over confirmed. The writers apparently made adjustments in the background to account for differences in population sizes, but the final paper only contains the adjusted estimates. So these are not perfect.
However, working backwards.
58.5% of Men are too heavy (overweight or obese by BMI), 77.7% of men are miscategorized across that boundary. So 45.5% of all men were too heavy and miscategorized. However, in aggregate the authors claim that only 37.4% of men were miscategorized. So there's some issue with either rounding or confidence intervals that I can't work back from in the data. Either way, that reasonably confirms that all, or very very close to all, of the people miscategorized were at the overweight/obese boundary and not the ideal/overweight boundary.
For women it's closer. 58.5% of women are too heavy. 62.8% of those are miscategorized. So 21.7% of women are both too heavy and miscategorized. But the authors say 26.1% of all women are miscategorized. Again, I suspect there are errors because of background weighting. But it clearly shows that women miscategorized among the too heavy greatly outnumber those miscategorized at the ideal/overweight boundary. By an order of magnitude (10:1) most likely.
Again, this is all very rough, because I don't have the raw data, I can only work backwards from the final calculations, which are weighted to account for difference in the number of participants in different demographics, normal.
If I had more time I could maybe work backwards further using their confidence intervals and other statistical measures presented, but I wanted to pull this together in less than an hour.
Anybody is welcome to work their own numbers if they like.1 -
There is nothing wrong with BMI as a measure, it is what it claims to be....a statistical distribution. People just don't know how to interpret statistical distributions.
BMI is just your weight divided by your height. At somepoint it was done for a sample set of a population that was also rated for whether or not they were considered to be overweight, underweight, obese, morbidly obese etc.
They determined that if your BMI was 25+ you were overweight within that distribution. What that means is that for joe shmoe you pull off the street if you ask their weight (which they will know roughly), their height (which they will know roughly) and you divide those numbers and get their BMI and that BMI is over 25 then most likely they are overweight.
The fact that not all people fall into the center of that distribution and that someone who has a ton of muscle mass and very low bodyfat will appear as having an "overweight" BMI does not somehow invalidate BMI.
All BMI is is a quick way to estimate things like obesity within populations based off of statistical distributions. It is a way of converting a large dataset of collected height/weight info (which is commonly available) and converting it into a measure of percent obesity within a population (which is info not commonly available). If you use it for that purpose then it is quite accurate. If you use it as your own personal target for weight gain/loss regardless of your body composition then that is you misunderstanding what BMI is for, not BMI being "wrong".
People misusing a tool does not somehow invalidate it as a useful tool.
To answer the title of the thread, no...not everyone is intended to be in the "healthy" BMI range, that isn't what BMI is for. Its a tool for making inferences based on large datasets based on statistical population distributions...it is not a tool to set a goal for yourself.12 -
JerSchmare wrote: »I hate these threads. Generally, BMI is a good indicator, but not always. There are other factors. However, most overweight people think they’re an outlier, but they’re not, they’re just simply overweight.
As someone who works with hundreds of overweight people per year, I have found that almost no one actually thinks this way. They all know they are overweight.
do you really think that those who think they are outliers are seeking help? no they are not...they think they are fine the way they are (as far as weight goes) so why would they seek out you???? and ergo how could you have conversations with them....
I didn’t say they were “seeking help”. They are coming in for fitness assessments. I’ve done lots of them-as well as numerous screenings—on people of all shapes, sizes, and motivations. I’ve likely done more body composition assessments than anyone on these forums-maybe even more than everyone combined.
This stereotypical fat person who denies their obesity and claims to have “big bones” doesn’t exist in any significant number.
They are far, far, far, far outnumbered by those who-on both the low end and the high end—are confused because they know their bodies are different, and are constantly being judged by people —but don’t understand exactly why or how their bodies fit in the continuum of body types.
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GottaBurnEmAll wrote: »1st one is an abstract and is from 2002...almost 20 years old????
I'm sure you are capable of finding the full article and reading it. I know I managed to do it. And I'm not sure why you have an issue with an article published 15 years ago. Unless time itself invalidates science.
Except the first study does. And I didn't make any assertion in particular giving a number, you must be confusing me with another poster. HOWEVER...and it doesn't address your assertion that bone size difference can account for 8+lbs in body weight variance of two people who are same gender, height and race.
How is it that you can recognize interracial genetic frame differences that result in real health outcome differences related to BMI, but cannot accept that individual variation within populations is also real and significant?and the 2nd one doesn't prove anything about your original assertion either...we know that Asians have a different BMI scale than we do and has nothing to do with your original argument or the original post...
I don't argue that for an "average human being", whatever that is, BMI is a rough indicator of body fat. I do argue:My original assertion..BMI is a good measure for the average population and that there are few outliers in that population...and that it is not "bone size" that will account for people being categorized as overweight or obese it's fat.
1. that the cutoff of 25 is arbitrary and not supported by morbidity and morality data for all populations. The existence of separate recommendations for Asians is evidence.
2. The BMI scale itself is flawed because it assumes a relationship of height to volume (mass) of h*h while volume is a cubic relationship. Being stochastically fitted for a height of 5' even, the error is linearly increasing with deviation from that height. This is not particularly controversial from a mathematics standing.
3. As a matter of mathematical interest, if my bones alone, never mind the volume of everything else in me, account for 15% of my mass, and my friend's bones are 12% of hers, then exactly 7.6 lbs of our weight difference is just bones. Now, personally, I find it really stupid that if I gain 10 lbs I'm classified as "overweight" but she has to gain 35 lbs to be "overweight". Because my body is clearly larger in frame and muscle. That is a pretty good illustration of the arbitrary nature of BMI when applied to individuals not populations.
4. Also on that matter, the fit of BMI to body fat is considered generally good... To one standard deviation. That's 68%. OK, great. That means if the population is normally distributed 32% are outliers.
If you found the article why link in the abstract????
2nd point you responded to me saying 8lbs of bone was a bit much imo with a negative assertion that it was possible based on you and your friend and there are 2 links...1 is an abstract that doesn't prove it and neither does the 2nd.
No where did I say frame size of people was all the same...I said 8lbs of it was a bit much imo and that for those people claiming frame size keeps them in the overweight of bmi they were in denial...perhaps you have me confused with another poster.
Now onto the meat of it.
comparing 12% for your friend and 15% is flawed...apples to apples.
and perhaps you are one of those individuals who is in denial because you are almost in the overweight category????and that is causing a bias in your argument...been there done that until I wasn't in the overweight category and still wearing a size 8 shoe...and still "big boned" but a hella lot less fat.
I think accusing someone of being “in denial” about their body because you disagree with them on a point of them on a point of science is out of line and deserves an apology.
I am not disagreeing on a point of science. She disagreed and argued that she is "bigger" because of bone size...I say no way...people who think that are in denial and are more fat than they want to admit.
Point of science is this.
BMI is a good measure for the average person (at least it is currently)
12-15% of the body weight of a person is from bone no more no less.
if you are in the overweight category for BMI it's not from bones...chances are you are overfat (unless an outlier who has exceptional muscle mass) and yes I will say that there are those who are outlier.
This poster is not.
ETA: so no apology will be forthcoming from me.
That poster isn't overweight. She's within healthy range for BMI. You just moved the goalposts. She's near the top range for her BMI because she has a large frame.
She's not in denial and yes, you do owe her an apology.
1. I never said she didn't have a large frame.
2. She contended bmi is not valid due to bone size which is invalid.
3. I never said she was over weight I said she might be on the top end because she had more weight than she wants to admit aka denial.
And I will not apologize for that.
I will stand by my original statement that those who say bmi doesn't apply to them are most likely in denial as the outliers are not that common.
People who are not educated in exercise science often use “bone size” as a substitute for “higher LBM”, since they are not familiar with other terminology. Fixating on their use of “bone size” because it is not precisely accurate confuses the issue
I can say with 100% certainty that the number of “outliers” from the BMI ranges is at least 20%. I can also say with 100% certainty that the actual number of people “in denial” about their weight is less than 10%.
Most of the people who have unrealistic expectations about their weight are those with “large frames” who think they can/should be able to reach the lower end of the BMI range for their height.
nope and nope.
First, you absolutely can't say that with any certainty. You say that from your gut, because it SEEMS that way to you. But I challenge you to find a study that supports either of those suppositions.
You can "believe" them if you chose to. But there is a high probability that you are wrong on both counts.
On this particular subject, I have enough data points that I can speak with a reasonable level of expertise. I don’t make statements like that casually.
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Just go to any public beach. You'll get visual verification (sometimes might make your eyes burn) that 70% of the population is overweight/obese and as many or more are overfat (even at a "normal' bmi).2
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1. I never said she didn't have a large frame.
2. She contended bmi is not valid due to bone size which is invalid.
3. I never said she was over weight I said she might be on the top end because she had more weight than she wants to admit aka denial.
And I will not apologize for that.
I will stand by my original statement that those who say bmi doesn't apply to them are most likely in denial as the outliers are not that common.
People who are not educated in exercise science often use “bone size” as a substitute for “higher LBM”, since they are not familiar with other terminology. Fixating on their use of “bone size” because it is not precisely accurate confuses the issue
I can say with 100% certainty that the number of “outliers” from the BMI ranges is at least 20%. I can also say with 100% certainty that the actual number of people “in denial” about their weight is less than 10%.
Most of the people who have unrealistic expectations about their weight are those with “large frames” who think they can/should be able to reach the lower end of the BMI range for their height.
I feel I have a couple of points to clarify.
Sezxy: I did not say BMI is "not valid" (in total). I said it has QUALIFIED use. Which is to say it's not (as Aaron pointed out above) a tool that was designed or meant to be applied to judge any individual's health, but rather a good judge of populations, and a rough estimate for people who fall within a standard deviation of the mean for all body aspects (hip width, bone density, musculature, etc).
A detailed defense of my not being in denial is following in the spoiler.I hate to take this detour. I felt the point that I was not in denial was well-defended by others, I really don't understand why you had to throw it in. But since it's now been hammered on (though it isn't salient) let me put this here:- current height 5'8.25" - weight 155 lbs . BMI = 23.4
- tallest height 5'11" BMI = 21.6
- doctor-estimated real height 6'1" BMI = 20.4
Between the two of us, if our bone density falls at opposite ends of the normal range of most people, which seems likely, that difference alone accounted for nearly 8 lbs, your arbitrary "impossible" number. I imagine the rest of it is mostly lean body mass difference, though not all.. I do have a rather generous bosom even now, after all (34 DD to her 32 A). However, I am quite lean at this point. You can see shadows from my ribs front, back and side. I've got that hip bone ridge thing going on (wow does that hurt if I bump into something!), a flat stomach, and am starting to show muscle definition in my arms, calves, thighs, and abs. As a large-framed individual (by both current wrist and ankle measurements) that shouldn't be overly surprising.
It remains a valid observation that for an arbitrary weight cutoff uniform to all people of a given height that I will be far leaner than she would be at that given weight; and that means that health effects due to having too much adiposity would kick in for her at a much lower absolute weight than I. You can argue about the need to label her "overweight" at a lower weight, which may be and was the impetus for WHO recommendations to lower SOME Asian regions' cutoffs (interestingly they actually raised the cutoff for others!)
WHO, E. C. (2004). Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies. Lancet (London, England), 363(9403), 157.
The WHO has made available a PDF of the above citation for personal use only.
Now, if the WHO has taken the position that, for example, it is appropriate to label rural Thailanders "overweight" only above a BMI of 27, why is it such a contentious idea that there are other populations that demonstrate similarly higher risk-weight profiles?
Adzak, "bone size" is a real thing. People's bones vary in density. Weight is not the only thing that will create denser bones, any repeated, load-bearing stress (such as heavy work or weight lifting) will do the same thing. It doesn't generally account for everything, but I demonstrated that frame size (which refers to the overall breadth of skeletal structure) can account for considerable weight differences (just under 8 lbs) at the far ends of people considered to be within normal frame distribution. I specifically did not calculate the differences in other lean body mass aspects, such as organs or muscles, because the calculations would've required even more research, and because 8 lbs was the arbitrary weight differential that I was replying to.
p.s.
Holy Mother of Nested Quotes, Batman! I think I cut 8 or 9 layers out there to make this reply legible
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distinctlybeautiful wrote: »Ok maybe BMI wasn’t the best way to frame it. What I’m hearing though is that y’all generally believe there is an ideal body weight / body size / body fat percentage range that people should be in? And that being outside that range indicates less-than-optimal health? And that people should strive to be close to or within this range?
There is definitely such a thing as being at a healthy weight and being at an unhealthy weight. What that is looks different on different people. Many models, including so called fitness models, are unhealthy because they are underweight - however, since this lacks the same stigma in society, you don't see them trying to fatten up, even though they may have lost their periods and have osteoporosis. I had problems with fainting, anemia, and reactive hypoglycemia when I was underweight as a teen model.
And then there's obesity. Recent research indicates that even apparently healthy obese people are at heightened risk for several health conditions.
I can say, speaking for myself, that not only am I healthier at "normal" BMI, but that I feel a distinct change in my ability to perform as an athlete at almost exactly the dividing lines of the BMI chart. When I was morbidly obese I could barely function. When I was obese, I could walk but not run easily or jump or touch my toes. When I hit overweight, I could do those things but I could also tell I wasn't doing them as well as I potentially could. I recently hit the top end of normal BMI and can do things like bend over and touch my forehead to my knees, without my gut being in the way. Running is much easier.
However, it's pretty much coincidence that my body type coincides closely with the BMI chart, and it doesn't work so well for everyone.
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JerSchmare wrote: »I hate these threads. Generally, BMI is a good indicator, but not always. There are other factors. However, most overweight people think they’re an outlier, but they’re not, they’re just simply overweight.
As someone who works with hundreds of overweight people per year, I have found that almost no one actually thinks this way. They all know they are overweight.
do you really think that those who think they are outliers are seeking help? no they are not...they think they are fine the way they are (as far as weight goes) so why would they seek out you???? and ergo how could you have conversations with them....
I didn’t say they were “seeking help”. They are coming in for fitness assessments. I’ve done lots of them-as well as numerous screenings—on people of all shapes, sizes, and motivations. I’ve likely done more body composition assessments than anyone on these forums-maybe even more than everyone combined.
This stereotypical fat person who denies their obesity and claims to have “big bones” doesn’t exist in any significant number.
They are far, far, far, far outnumbered by those who-on both the low end and the high end—are confused because they know their bodies are different, and are constantly being judged by people —but don’t understand exactly why or how their bodies fit in the continuum of body types.
It doesn't matter why they are there to see you...you cannot say with 100% accuracy anything of the sort.
I know lots who say "I am not overweight just big boned"...heck I used to be one...who said..."I won't get any smaller than X because I am big boned so BMI is not valid"
and there are lots in my life who have said it too and here and in the general public.
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Aaron_K123 wrote: »There is nothing wrong with BMI as a measure, it is what it claims to be....a statistical distribution. People just don't know how to interpret statistical distributions......All BMI is is a quick way to estimate things like obesity within populations based off of statistical distributions. It is a way of converting a large dataset of collected height/weight info (which is commonly available) and converting it into a measure of percent obesity within a population (which is info not commonly available). If you use it for that purpose then it is quite accurate. If you use it as your own personal target for weight gain/loss regardless of your body composition then that is you misunderstanding what BMI is for, not BMI being "wrong".
People misusing a tool does not somehow invalidate it as a useful tool.
To answer the title of the thread, no...not everyone is intended to be in the "healthy" BMI range, that isn't what BMI is for. Its a tool for making inferences based on large datasets based on statistical population distributions...it is not a tool to set a goal for yourself.
The sad part about this is that many in the health field don't seem to get this. For instance, my company has a healthy living program going on to try to encourage folks to be healthier (less cost to the company that way, of course). The company running the program, called Provant, sets markers for what they consider to be healthy. One of their die-hard, set in stone markers is BMI. They've only recently added waist circumference as a second measure, but if you want the credit, you still have to be within the BMI number, with no modifiers available whatsoever.
Another frustrating thing to me about Provant is that their ideal healthy range in other areas don't match up. For instance: they will not credit you for having good HDL unless its above 60, though the American Heart Association says that while above 60 is ideal, anything above 40 is normal.
Their dietary advance is pretty much the food pyramid as well. *sigh* but if I want cheaper health insurance, I have to jump through as many hoops as I can with this outfit.1 -
1. I never said she didn't have a large frame.
2. She contended bmi is not valid due to bone size which is invalid.
3. I never said she was over weight I said she might be on the top end because she had more weight than she wants to admit aka denial.
And I will not apologize for that.
I will stand by my original statement that those who say bmi doesn't apply to them are most likely in denial as the outliers are not that common.
People who are not educated in exercise science often use “bone size” as a substitute for “higher LBM”, since they are not familiar with other terminology. Fixating on their use of “bone size” because it is not precisely accurate confuses the issue
I can say with 100% certainty that the number of “outliers” from the BMI ranges is at least 20%. I can also say with 100% certainty that the actual number of people “in denial” about their weight is less than 10%.
Most of the people who have unrealistic expectations about their weight are those with “large frames” who think they can/should be able to reach the lower end of the BMI range for their height.
I feel I have a couple of points to clarify.
Sezxy: I did not say BMI is "not valid" (in total). I said it has QUALIFIED use. Which is to say it's not (as Aaron pointed out above) a tool that was designed or meant to be applied to judge any individual's health, but rather a good judge of populations, and a rough estimate for people who fall within a standard deviation of the mean for all body aspects (hip width, bone density, musculature, etc).
A detailed defense of my not being in denial is following in the spoiler.I hate to take this detour. I felt the point that I was not in denial was well-defended by others, I really don't understand why you had to throw it in. But since it's now been hammered on (though it isn't salient) let me put this here:- current height 5'8.25" - weight 155 lbs . BMI = 23.4
- tallest height 5'11" BMI = 21.6
- doctor-estimated real height 6'1" BMI = 20.4
Between the two of us, if our bone density falls at opposite ends of the normal range of most people, which seems likely, that difference alone accounted for nearly 8 lbs, your arbitrary "impossible" number. I imagine the rest of it is mostly lean body mass difference, though not all.. I do have a rather generous bosom even now, after all (34 DD to her 32 A). However, I am quite lean at this point. You can see shadows from my ribs front, back and side. I've got that hip bone ridge thing going on (wow does that hurt if I bump into something!), a flat stomach, and am starting to show muscle definition in my arms, calves, thighs, and abs. As a large-framed individual (by both current wrist and ankle measurements) that shouldn't be overly surprising.
It remains a valid observation that for an arbitrary weight cutoff uniform to all people of a given height that I will be far leaner than she would be at that given weight; and that means that health effects due to having too much adiposity would kick in for her at a much lower absolute weight than I. You can argue about the need to label her "overweight" at a lower weight, which may be and was the impetus for WHO recommendations to lower SOME Asian regions' cutoffs (interestingly they actually raised the cutoff for others!)
WHO, E. C. (2004). Appropriate body-mass index for Asian populations and its implications for policy and intervention strategies. Lancet (London, England), 363(9403), 157.
The WHO has made available a PDF of the above citation for personal use only.
Now, if the WHO has taken the position that, for example, it is appropriate to label rural Thailanders "overweight" only above a BMI of 27, why is it such a contentious idea that there are other populations that demonstrate similarly higher risk-weight profiles?
Adzak, "bone size" is a real thing. People's bones vary in density. Weight is not the only thing that will create denser bones, any repeated, load-bearing stress (such as heavy work or weight lifting) will do the same thing. It doesn't generally account for everything, but I demonstrated that frame size (which refers to the overall breadth of skeletal structure) can account for considerable weight differences (just under 8 lbs) at the far ends of people considered to be within normal frame distribution. I specifically did not calculate the differences in other lean body mass aspects, such as organs or muscles, because the calculations would've required even more research, and because 8 lbs was the arbitrary weight differential that I was replying to.
p.s.
Holy Mother of Nested Quotes, Batman! I think I cut 8 or 9 layers out there to make this reply legible
I will be very blunt with you on this topic.
YOu used yourself and a friend to illustrate how bone size can impact BMI (which was not part of my original argument) without adding in that you personally are an Outlier due to a medical condition.
and if you had revealed that a lot of our discussion wouldn't have happened but of course your comparison wouldn't have held water either.....
My original premise was thisI always find those that dismiss BMI as a decent measure for the average person usually don't fall in the healthy range and either believe it's due to "bone" size etc or are in denial about their weight.
There are outliers in the world and they will fall outside the "health range" but not often and not for their entire life.
I used to think I would never fit in the healthy range due to "bone size'...psh...I was so in denial about being overweight/fat.
so for this part of the "debate" you and I will have to come to terms with a couple of things.
1. I said that there were outliers to start with
2. your argument was when I questioned if a certain # of pounds of a persons weight could be bone
3. you neglected to do a fair comparison because of 4
4. you neglected to reveal your were an outlier
and so what this has become is non sense and I am not going to respond further to this subdebate of this particular thread. If you choose to that is fine but I won't be.
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JerSchmare wrote: »I hate these threads. Generally, BMI is a good indicator, but not always. There are other factors. However, most overweight people think they’re an outlier, but they’re not, they’re just simply overweight.
As someone who works with hundreds of overweight people per year, I have found that almost no one actually thinks this way. They all know they are overweight.
do you really think that those who think they are outliers are seeking help? no they are not...they think they are fine the way they are (as far as weight goes) so why would they seek out you???? and ergo how could you have conversations with them....
I didn’t say they were “seeking help”. They are coming in for fitness assessments. I’ve done lots of them-as well as numerous screenings—on people of all shapes, sizes, and motivations. I’ve likely done more body composition assessments than anyone on these forums-maybe even more than everyone combined.
This stereotypical fat person who denies their obesity and claims to have “big bones” doesn’t exist in any significant number.
They are far, far, far, far outnumbered by those who-on both the low end and the high end—are confused because they know their bodies are different, and are constantly being judged by people —but don’t understand exactly why or how their bodies fit in the continuum of body types.
It doesn't matter why they are there to see you...you cannot say with 100% accuracy anything of the sort.
I know lots who say "I am not overweight just big boned"...heck I used to be one...who said..."I won't get any smaller than X because I am big boned so BMI is not valid"
and there are lots in my life who have said it too and here and in the general public.
“The guide invited a crowd to imagine that they were looking across a desert at a mountain range on a day that was twinkling bright and clear. They could look at a peak or a bird or a cloud, at a stone right in front of them, or even into a canyon behind them. But among them was this poor Earthling, and his head was encased in a steel sphere which he could never take off. There was only one eyehole through which he could look, and welded to that eyehole were six feet of pipe.
This was only the beginning of Billy’s miseries in the metaphor. He was also strapped to a steel lattice which was bolted to a flatcar on rails, and there was no way he could turn his head or touch the pipe. The flat end of the pipe rested on a bi-pod which was also bolted to the flatcar. All Billy could see was the little dot at the end of the pipe. He didn’t know he was on a flatcar, didn’t even know there was anything peculiar about his situation.
The flatcar sometimes crept, sometimes went extremely fast, often stopped–went uphill, downhill, around curves, along straightaways. Whatever poor Billy saw through the pipe, he had no choice but to say to himself, ‘that’s life.’”7 -
Absolutely not. I'm using mfp to lose weight, however when I was younger I was slim and in good shape, I'm 5'8 and weighed 13stone. My bmi indicated I was obese. Now I weigh 15st 4lb I'm a bit podgy yet my bmi indicates I'm morbidly obese. Some people have denser bones than others, and I don't mean big bones. I mean the density ie weight.7
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The_Gruffet wrote: »Absolutely not. I'm using mfp to lose weight, however when I was younger I was slim and in good shape, I'm 5'8 and weighed 13stone. My bmi indicated I was obese. Now I weigh 15st 4lb I'm a bit podgy yet my bmi indicates I'm morbidly obese. Some people have denser bones than others, and I don't mean big bones. I mean the density ie weight.
Your bone density isn't pushing you into the "morbidly obese" range unless you are related to the Wolverine and have an Adamantium skeleton.8 -
JerSchmare wrote: »I hate these threads. Generally, BMI is a good indicator, but not always. There are other factors. However, most overweight people think they’re an outlier, but they’re not, they’re just simply overweight.
As someone who works with hundreds of overweight people per year, I have found that almost no one actually thinks this way. They all know they are overweight.
do you really think that those who think they are outliers are seeking help? no they are not...they think they are fine the way they are (as far as weight goes) so why would they seek out you???? and ergo how could you have conversations with them....
I didn’t say they were “seeking help”. They are coming in for fitness assessments. I’ve done lots of them-as well as numerous screenings—on people of all shapes, sizes, and motivations. I’ve likely done more body composition assessments than anyone on these forums-maybe even more than everyone combined.
This stereotypical fat person who denies their obesity and claims to have “big bones” doesn’t exist in any significant number.
They are far, far, far, far outnumbered by those who-on both the low end and the high end—are confused because they know their bodies are different, and are constantly being judged by people —but don’t understand exactly why or how their bodies fit in the continuum of body types.
It doesn't matter why they are there to see you...you cannot say with 100% accuracy anything of the sort.
I know lots who say "I am not overweight just big boned"...heck I used to be one...who said..."I won't get any smaller than X because I am big boned so BMI is not valid"
and there are lots in my life who have said it too and here and in the general public.
“The guide invited a crowd to imagine that they were looking across a desert at a mountain range on a day that was twinkling bright and clear. They could look at a peak or a bird or a cloud, at a stone right in front of them, or even into a canyon behind them. But among them was this poor Earthling, and his head was encased in a steel sphere which he could never take off. There was only one eyehole through which he could look, and welded to that eyehole were six feet of pipe.
This was only the beginning of Billy’s miseries in the metaphor. He was also strapped to a steel lattice which was bolted to a flatcar on rails, and there was no way he could turn his head or touch the pipe. The flat end of the pipe rested on a bi-pod which was also bolted to the flatcar. All Billy could see was the little dot at the end of the pipe. He didn’t know he was on a flatcar, didn’t even know there was anything peculiar about his situation.
The flatcar sometimes crept, sometimes went extremely fast, often stopped–went uphill, downhill, around curves, along straightaways. Whatever poor Billy saw through the pipe, he had no choice but to say to himself, ‘that’s life.’”
look in the mirror much?
perhaps instead of trying to convince me I am wrong about this and you are 100% accurate accept that there are no absolutes and you stepped in it...
I get that there are those who are in tune with themselves and know that they are overweight/fat and not in denial...I didn't say 100% of the people who bmi didn't apply to were in denial...
see how we are different here...you are 100% sure...and if you need a reminder that you said 100% I can go get the quote5
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