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Is every single body in the world intended to be within the so-called healthy BMI range?

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Replies

  • tomteboda
    tomteboda Posts: 2,171 Member
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  • jesspen91
    jesspen91 Posts: 1,383 Member
    I actually think that BMI is more often a poor indicator in the opposite direction than people think. I carry all my weight around my middle so even once I got to a healthy weight by BMI standards, I still had a 33.5 inch waist (at 5 ft 3) and would not say that I was healthy. I am now 10lbs below the top end of BMI and have finally got my waist below 30 inches. If I had stopped losing weight at a healthy BMI I would still be at risk of all the health problems associated with visceral fat.
  • SezxyStef
    SezxyStef Posts: 15,270 Member
    SezxyStef wrote: »
    Azdak wrote: »
    SezxyStef wrote: »
    tomteboda wrote: »
    SezxyStef 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.
    SezxyStef wrote: »
    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.
    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...
    SezxyStef wrote: »
    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...
    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?
    SezxyStef wrote: »
    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.
    I don't argue that for an "average human being", whatever that is, BMI is a rough indicator of body fat. I do argue:
    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.

    Is she more fat than she wants to admit?

    is she in the overweight range?
  • bmeadows380
    bmeadows380 Posts: 2,983 Member
    Also, size 8 feet (I'm assuming US sizing?) isn't large at all. It's average. It's on of the sizes that sells out fastest because it's the most common size (actually more like 7-8 but leaning more towards 8 now because we're all bigger).

    Yours,

    Someone who has worked in shoe retail more times than I'd ever hoped.

    yes, I know size 8 in US sizing isn't large at all. That's why I said I'd love to be in a size 8. I am in a US size 11/12, which is definitely considered large for a female

    That response wasn't aimed at you but at Stef who said she had big feet.

    ah! my apologies - the way the MFP groups together quotes had mine as the last quote showing. sorry!
  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    edited November 2017
    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).
  • mfpchris
    mfpchris Posts: 279 Member
    It is statistics. A 99% confidence interval. There is a 99% chance that an optimally healthy weight for you is within that range.
  • GottaBurnEmAll
    GottaBurnEmAll Posts: 7,722 Member
    mfpchris wrote: »
    It is statistics. A 99% confidence interval. There is a 99% chance that an optimally healthy weight for you is within that range.

    Nope.
    lemurcat12 wrote: »
    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).

  • lemurcat12
    lemurcat12 Posts: 30,886 Member
    Not everyone here is fat. Most of the people in this discussion about BMI are within the healthy range.