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How do we judge a healthy weight range? BMI is no longer valid?

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Replies

  • ForecasterJason
    ForecasterJason Posts: 2,577 Member
    This just in: people in denial about their size and/or health think the measure telling them they are in denial is inaccurate?

    And people with poor reading comprehension make inaccurate assumptions. Your point would be?

    No.

    Some day you'll figure it out and stop kidding yourself. Or you won't. Either way, no skin off my back.
    The numbers say that if I were under 25 BMI I would also be below average in muscle mass for my weight. The numbers say that if I can achieve 15% body fat at 220 pounds, my muscle mass percentage will be close to the middle of average.
    I don't understand this. Out of curiosity, how large are your wrists? I would say your bone structure must be massive for what you're saying to be true. I don't have access to it right now, but a few weeks ago I found a percentile chart for adults for lean body mass. I highly doubt you would fall in the lower end of the range.

  • MissusMoon
    MissusMoon Posts: 1,900 Member
    edited August 2016
    Demaniacle wrote: »
    BMI appears to be a good guideline for most people; however, the issue with BMI is that there are many factors it does not take into account. For example, muscle mass is not well-accounted for, so it's quite possible to have someone who falls in the overweight category prescribed by the BMI scale, but is actually quite fit and lean-looking. Also, frame size is not factored in, either. Someone who is 'smalled-boned' is going to wear the same amount of weight differently than someone who is 'big-boned', assuming all other variables are held constant (height, gender, muscle:fat ratio, etc.).
    There is also a great amount of individual variation that BMI cannot account for. What looks good/is healthy/functional for one person is not going to be the same for another person.

    I know from scans that I am "big boned". The radiologist and my doctor both said that accounts for a very small variance in weight. A couple of pounds, tops.

    You are overstating the differences in people as they relate to BMI. People use extreme and rare outlier examples.
    BMI's that are too low (sub 19) or over 27 are consistently proven to be indicators for serious health consequences.
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  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    Dove0804 wrote: »

    Had you read and understood everyone else's posts, and had decent reading comprehension skills yourself, you would understand that your personal goals are that of an extreme outlier and will be very hard to achieve and maintain.

    15% body fat is borderline athletic for a male. 40% muscle mass is in the middle of average. Not an extreme outlier on either of these accounts. 6'1" and large frame puts me on the top end of normal, not an extreme outlier. The only way I could possibly be an extreme outlier is if my bone and organ density is off the chart. I suppose this is possible, I don't really know, but I highly doubt it.

  • 3dogsrunning
    3dogsrunning Posts: 27,167 Member
    I think we should all just throw darts at a board to decide.

    It's not that hard, really. There is no one "ideal" weight for an individual. If you are generally within your BMI normal range or slightly outside the bounds, if your waist is not relatively large, if you like what you see in the mirror, if your health parameters are fine, then you are likely fine.

    BMI is not meant as a diagnostic tool, neither are other things like body fat. Some people may benefit from additional weight like those with bone density issues, other people may benefit from being skinnier than average like those with T2 diabetes. Some people are generally in good health and their "ideal" weight is solely based on aesthetics. For some people being overly muscular is good for their purposes like for body builders, for others being overly muscular is detrimental to their performance like for endurance athletes. It's a sliding scale for individuals, really, people just like to argue the minutia.

    It was a joke.

    I've been saying the same thing you just did the whole time.
  • Dove0804
    Dove0804 Posts: 213 Member
    edited August 2016
    Dove0804 wrote: »

    Had you read and understood everyone else's posts, and had decent reading comprehension skills yourself, you would understand that your personal goals are that of an extreme outlier and will be very hard to achieve and maintain.

    15% body fat is borderline athletic for a male. 40% muscle mass is in the middle of average. Not an extreme outlier on either of these accounts. 6'1" and large frame puts me on the top end of normal, not an extreme outlier. The only way I could possibly be an extreme outlier is if my bone and organ density is off the chart. I suppose this is possible, I don't really know, but I highly doubt it.

    The problem is, you are solely looking at body fat percentage and ignoring total body weight (and every other parameter out there). 15% body fat is not an outlier in and of itself, but the work to achieve and maintain 15% body fat at various weights is definitely not equal. You are talking as if there's a whole slew of people out there who are able to be at a high weight but still maintain a low body fat percentage. This is simply not the case. Those who exist are outliers, and BMI would not apply to them. This is not reasonable to expect of the majority of the population.
  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    By the way, this vegan would like a word...

    article_NANBF_6.jpg

    (Sorry, I had to)

    He represents maybe a percent of a percent of vegans?

  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    The numbers say that if I were under 25 BMI I would also be below average in muscle mass for my weight. The numbers say that if I can achieve 15% body fat at 220 pounds, my muscle mass percentage will be close to the middle of average.
    I don't understand this. Out of curiosity, how large are your wrists? I would say your bone structure must be massive for what you're saying to be true. I don't have access to it right now, but a few weeks ago I found a percentile chart for adults for lean body mass. I highly doubt you would fall in the lower end of the range.

    My wrist is just under 8 inches, measured between my hand and the protrusions of the bones on either side of the joint. So 7-7/8".

    I'm basing my calculations on my mass minus fat and muscle percentages as measure by my bio impedance scale. I'll mention again, that at present time, the body fat percentage reported by the scale is within a couple tenths of my BMI number. So I'll concede that the fatter one is, the more accurate BMI seems to be as an estimate of body fat.

    Just for completeness, I'll throw all the math on here. I'm at 262# total. BF% is 34.6 = 90.7# (rounding). Muscle% is 29.5 = 77.3# Remaining lean mass is then 94#. Since I'm an adult and no longer growing, this number should stay the same regardless of what I weigh (barring bone loss in old age). Stated previously, I'm 6'1".

    To achieve a BMI of 24.4, I would have to weigh 185#. If I was at 15% body fat at that weight it would be 27.75# fat + 94# static lean mass = 121.75# non-muscle. Remaining muscle mass of 63.25# = 34% of total mass.
    The first source I was able to find that gave an actual percentage for average muscle mass (link given in a previous post) states that the average for men is between 38 and 54 percent. Thus at a BMI just short of "overweight", and 15% actual body fat, I would be below average for muscle mass.

    On the other hand, if I weighed 220# at 15% body fat, it would leave me with 33# of fat. That plus the 94# of static weight subtracted from 220 leaves 93# of muscle which is 42% of total mass... right in the average range.
    I just now found another site specifying percentages of muscle mass.
    https://quora.com/On-average-what-of-a-persons-lean-body-mass-total-mass-minus-fat-mass-consists-of-muscle
    This one gives average muscle mass for men as being 50% of lean body mass and 40% of total body mass +/- 5%... just what I have calculated.


    I found the link above while looking unsuccessfully for numbers regarding the average non-muscle lean mass. The biggest margin for error in my math would be if my scale were grossly under-reporting my muscle mass or grossly over-reporting my BF% (which would also make the BMI number inaccurate).
    If neither of these is the case, then for me to qualify as an extreme outlier my non-muscle lean mass would have to be significantly above average for my height and gender. I'm big, but I'm not Andre the Giant. Nor am I Gimli, with a bone density comparable to granite (so far as I know).

    So there we have it -MATH-. If someone can site sources showing that my current lean body mass is drastically above the norm for my height and gender, I'm all eyes.
  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    RLester67 wrote: »
    From your link
    BMI, or body mass index, is an estimated measure of the fat composition of the human body, or how proportionate a person's weight is to his height

    That's not the same as estimating actual bodyfat percentage.

    What is composition then, if not percentage? And if you read further on, it does actually state "percentage" down the page a ways.

    Livestrong also states that BMI is supposed to approximate body fat percentage. And they're a site I generally disagree with on a number of topics, as they promote low fat, high carb diets and low mass body compositions.

  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    edited August 2016
    Dove0804 wrote: »
    The problem is, you are solely looking at body fat percentage and ignoring total body weight (and every other parameter out there). 15% body fat is not an outlier in and of itself, but the work to achieve and maintain 15% body fat at various weights is definitely not equal. You are talking as if there's a whole slew of people out there who are able to be at a high weight but still maintain a low body fat percentage. This is simply not the case. Those who exist are outliers, and BMI would not apply to them. This is not reasonable to expect of the majority of the population.

    I'm also looking at muscle mass percentage. 40% in a male is -normal-, not a high weight.

    I'm also saying that what the "experts" and "authorities" are defining as high weight, is not necessarily high.

    I've put up my math. Let's see some solid numbers and evidence in support of the BMI definitions, because all I've seen so far is blind appeal to authority. The arguments boil down to, "nuh uh. You have to be doing it wrong because you disagree with the experts."
  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    Packerjohn wrote: »
    The type of scale you are using is notoriously inaccurate.

    Again, at my present weight, the scale and BMI are actually in agreement. If you are going to assume the scale is wrong, then BMI is also wrong.
    What I see in the mirror also agrees with being around 35% body fat.
  • litsy3
    litsy3 Posts: 783 Member
    edited August 2016
    litsy3 wrote: »


    In any case, using the highly scientific 'looking in the mirror and estimating' technique, I am nowhere near 18.5% fat. I'd say more like 20-21. 18.5 is pretty low for a woman.

    Your profile pic suggests you are a distance runner. Lower than average body fat often goes with the territory.

    I am a distance runner, but I'm nowhere near racing weight just now (and definitely not in that picture!) - that's what I'm doing hanging round on MFP!
  • Packerjohn
    Packerjohn Posts: 4,855 Member
    lemurcat12 wrote: »
    It makes no sense to think the BMI is supposed to BE body fat percentage, vs. an estimate of whether you have a healthy body fat percentage for the typical (not extremely muscular) person. For women, it's much more common to be within the BMI range and still overfat, because women having enough muscle to mess up BMI is rare (as others have pointed out). For men it's more common, but you'd know, and it's irrelevant for someone who is clearly obese -- as others have said, lose the weight and then decide.

    That BMI is not supposed to actually represent BF% can be demonstrated by the fat that under 18.5 is supposed to be underweight and that men and women have the same scale. Indeed, before it was adjusted, the scale for men being normal weight was slightly higher than women (20-27 vs. 19-26 or some such), when obviously no one has ever thought a man was underweight if below 20% BF.

    Excellent post. The BMI number does not equal bodyfat %

  • ForecasterJason
    ForecasterJason Posts: 2,577 Member
    This just in: people in denial about their size and/or health think the measure telling them they are in denial is inaccurate?

    And people with poor reading comprehension make inaccurate assumptions. Your point would be?

    No.

    Some day you'll figure it out and stop kidding yourself. Or you won't. Either way, no skin off my back.

    I'm not kidding myself. I am fat, and diabetic and my joints hurt. And I haven't at all denied it. That is why I'm counting calories and losing weight. As far as my goals, they are supported by math. The numbers say that if I were under 25 BMI I would also be below average in muscle mass for my weight. The numbers say that if I can achieve 15% body fat at 220 pounds, my muscle mass percentage will be close to the middle of average. And 15% body fat is not fat, period.

    I do not oppose BMI because I want to deny being fat. I oppose BMI because the charts designating a "healthy" weight range promote a low-muscle physique.

    Had you read and understood my posts up to this point, you would not have made that nonsense comment about 'denial' and I wouldn't be repeating these statements.

    If you're diabetic and your joints hurt the last thing you want to do is "maximize your muscle potential". Yes, having a good muscle mass is good for diabetes, but having too high of a muscle mass is still extra weight on the joints and bad for neuropathy. The amount of protein needed to maximize your muscle mass is also something to watch because diabetes can bring about impaired kidney function at any moment so it needs to be closely watched. Since you have stated you have a tendency to story visceral fat, having low subcutaneous fat may not be enough because you could be lean and muscular but still store a good amount of visceral fat if you are genetically predisposed.
    Good points. I think for muscle mass to effectively help diabetes one would need their amount of visceral fat to be minimized. And I don't know that diabetes risk has been studied for those who have taken their muscle mass to the upper limit.
  • Packerjohn
    Packerjohn Posts: 4,855 Member
    This just in: people in denial about their size and/or health think the measure telling them they are in denial is inaccurate?

    And people with poor reading comprehension make inaccurate assumptions. Your point would be?

    No.

    Some day you'll figure it out and stop kidding yourself. Or you won't. Either way, no skin off my back.

    I'm not kidding myself. I am fat, and diabetic and my joints hurt. And I haven't at all denied it. That is why I'm counting calories and losing weight. As far as my goals, they are supported by math. The numbers say that if I were under 25 BMI I would also be below average in muscle mass for my weight. The numbers say that if I can achieve 15% body fat at 220 pounds, my muscle mass percentage will be close to the middle of average. And 15% body fat is not fat, period.

    I do not oppose BMI because I want to deny being fat. I oppose BMI because the charts designating a "healthy" weight range promote a low-muscle physique.

    Had you read and understood my posts up to this point, you would not have made that nonsense comment about 'denial' and I wouldn't be repeating these statements.

    If you're diabetic and your joints hurt the last thing you want to do is "maximize your muscle potential". Yes, having a good muscle mass is good for diabetes, but having too high of a muscle mass is still extra weight on the joints and bad for neuropathy. The amount of protein needed to maximize your muscle mass is also something to watch because diabetes can bring about impaired kidney function at any moment so it needs to be closely watched. Since you have stated you have a tendency to story visceral fat, having low subcutaneous fat may not be enough because you could be lean and muscular but still store a good amount of visceral fat if you are genetically predisposed.
    Good points. I think for muscle mass to effectively help diabetes one would need their amount of visceral fat to be minimized. And I don't know that diabetes risk has been studied for those who have taken their muscle mass to the upper limit.

    Just my opinion but I would think that to take muscle mass to the upper limits a person would have to be eating a nutrionally sound diet and exercising. A couple of the things that tend to prevent diabetes
  • ForecasterJason
    ForecasterJason Posts: 2,577 Member
    Packerjohn wrote: »
    This just in: people in denial about their size and/or health think the measure telling them they are in denial is inaccurate?

    And people with poor reading comprehension make inaccurate assumptions. Your point would be?

    No.

    Some day you'll figure it out and stop kidding yourself. Or you won't. Either way, no skin off my back.

    I'm not kidding myself. I am fat, and diabetic and my joints hurt. And I haven't at all denied it. That is why I'm counting calories and losing weight. As far as my goals, they are supported by math. The numbers say that if I were under 25 BMI I would also be below average in muscle mass for my weight. The numbers say that if I can achieve 15% body fat at 220 pounds, my muscle mass percentage will be close to the middle of average. And 15% body fat is not fat, period.

    I do not oppose BMI because I want to deny being fat. I oppose BMI because the charts designating a "healthy" weight range promote a low-muscle physique.

    Had you read and understood my posts up to this point, you would not have made that nonsense comment about 'denial' and I wouldn't be repeating these statements.

    If you're diabetic and your joints hurt the last thing you want to do is "maximize your muscle potential". Yes, having a good muscle mass is good for diabetes, but having too high of a muscle mass is still extra weight on the joints and bad for neuropathy. The amount of protein needed to maximize your muscle mass is also something to watch because diabetes can bring about impaired kidney function at any moment so it needs to be closely watched. Since you have stated you have a tendency to story visceral fat, having low subcutaneous fat may not be enough because you could be lean and muscular but still store a good amount of visceral fat if you are genetically predisposed.
    Good points. I think for muscle mass to effectively help diabetes one would need their amount of visceral fat to be minimized. And I don't know that diabetes risk has been studied for those who have taken their muscle mass to the upper limit.

    Just my opinion but I would think that to take muscle mass to the upper limits a person would have to be eating a nutrionally sound diet and exercising. A couple of the things that tend to prevent diabetes
    I tend to agree. However, I think this becomes tricky for those that are already diabetic for the reasons amusedmonkey mentioned.

  • Packerjohn
    Packerjohn Posts: 4,855 Member
    Packerjohn wrote: »
    This just in: people in denial about their size and/or health think the measure telling them they are in denial is inaccurate?

    And people with poor reading comprehension make inaccurate assumptions. Your point would be?

    No.

    Some day you'll figure it out and stop kidding yourself. Or you won't. Either way, no skin off my back.

    I'm not kidding myself. I am fat, and diabetic and my joints hurt. And I haven't at all denied it. That is why I'm counting calories and losing weight. As far as my goals, they are supported by math. The numbers say that if I were under 25 BMI I would also be below average in muscle mass for my weight. The numbers say that if I can achieve 15% body fat at 220 pounds, my muscle mass percentage will be close to the middle of average. And 15% body fat is not fat, period.

    I do not oppose BMI because I want to deny being fat. I oppose BMI because the charts designating a "healthy" weight range promote a low-muscle physique.

    Had you read and understood my posts up to this point, you would not have made that nonsense comment about 'denial' and I wouldn't be repeating these statements.

    If you're diabetic and your joints hurt the last thing you want to do is "maximize your muscle potential". Yes, having a good muscle mass is good for diabetes, but having too high of a muscle mass is still extra weight on the joints and bad for neuropathy. The amount of protein needed to maximize your muscle mass is also something to watch because diabetes can bring about impaired kidney function at any moment so it needs to be closely watched. Since you have stated you have a tendency to story visceral fat, having low subcutaneous fat may not be enough because you could be lean and muscular but still store a good amount of visceral fat if you are genetically predisposed.
    Good points. I think for muscle mass to effectively help diabetes one would need their amount of visceral fat to be minimized. And I don't know that diabetes risk has been studied for those who have taken their muscle mass to the upper limit.

    Just my opinion but I would think that to take muscle mass to the upper limits a person would have to be eating a nutrionally sound diet and exercising. A couple of the things that tend to prevent diabetes
    I tend to agree. However, I think this becomes tricky for those that are already diabetic for the reasons amusedmonkey mentioned.

    Yep I was thinking more about those that lived the lifestyle long term.

  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    If you're diabetic and your joints hurt the last thing you want to do is "maximize your muscle potential".

    Who's maximizing? 42% is solidly within normal range. Yes, I wish to retain a solid mass and improve my functional strength to continue an active lifestyle. If I had a desk job and was less concerned with strength I might be ok with going as low as 205 (which would still be "overweight" by bmi). As it is, 220 is a more than 40 pound drop from where I am now, and I already have significantly reduced the pain due to the 30 I've lost so far. I also know (a few sessions of physical therapy have been a big help) that part of my low back issues is due to not enough strength in my lower abdominals.
  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    edited August 2016
    So, subtracting 40% muscle and 15% fat from your 220 pound goal, we arrive at 99 pounds.
    Do you think your skeleton and organs weigh 99 pounds?

    40% was a rounded number. My actual calculations for 220 work out to 42% muscle, with my calculations at current weight having given me 94 pounds non-muscle lean mass . And yes, I do believe that my total of bone, internal organs, skin, blood, blood vessels, nerves, cartilage, lymphatic system... (have I left anything out?) add up to 94 pounds. If you have references to dispute that, please post them.
  • MarkusDarwath
    MarkusDarwath Posts: 393 Member
    lemurcat12 wrote: »
    It makes no sense to think the BMI is supposed to BE body fat percentage, vs. an estimate of whether you have a healthy body fat percentage for the typical (not extremely muscular) person. ....For women, it's much more common to be within the BMI range and still overfat....,


    So it's a height to weight ratio with a poor correlation to body composition. This makes it useful to the individual, how? It's an equalizer for studies of large populations. It's only an indicator of healthy body composition when applied to the -mathematical average- of a group with a very large set of data points. You do understand that the ordinary common typical "average" person is not mathematically "average," correct? It is far too easy and common for a person to have a healthy composition outside the BMI range, or to have an unhealthy composition within the BMI range. And again, there's the fact that statistical studies of health outcomes compared to BMI show that actual risk levels do -not- correspond with the classifications on the standard BMI charts. The entire category of "overweight" is basically meaningless. It would be more accurate to simply eliminate that classification and place the cutoff between "normal" and "overfat" between 27 and 28,
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