Am I unhealthy? BMI says I'm obese..

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Replies

  • threewins
    threewins Posts: 1,455 Member
    Lillymoo01 wrote: »
    AnnPT77 wrote: »
    threewins wrote: »
    Lillymoo01 wrote: »
    threewins wrote: »
    There is a different BMI type calculation which uses height to the power of 2.5. Back in the day when BMI was invented powers of non-integers were hard to calculate, square is much easier.

    The equivalent calculation is 1.3 * weight / height ^ 2.5, this gives a number about 0.8 lower than the normal calculation for my body, I'm 183 cm tall.

    People can read about the new calculation here:

    https://people.maths.ox.ac.uk/trefethen/bmi.html

    There are a number of other indexes I've come across over the years, probably the most sophisticated which uses the height difference between shoulders and hips, and other measurements.

    This is my new weight range according to this.
    Your new BMI healthy range is
    38.57 to 52.11 kgs.

    There is no way I would consider myself healthy at under 40 kgs! I feel more comfortable with the current range between 41.5 and 55 kg, especially as I stop my periods under 42 kg.

    Which is why I really don't think that BMI should be used for individuals, as this graph shows

    3072julwrjhq.png

    The scatter graph shows that people of the same BMI can have vastly different body fat percentages.

    If the scatter graph is accurate, then the implication is that for women of BMI just over 30 (where OP is), it's quite unusual to have a BF% under 35%, which is at or (more commonly) above the BF% considered the healthy range for a 23-year-old, in most BF assessment schemes. Someone who's been training hard for a year is unlikely to have gained enough muscle mass from that short time to be an extreme outlier. Possible? Maybe. Likely? No.

    In general, the scatter graph would seem to suggest that BMI often under-diagnoses excessive body fat in women, considering them to be in a normal BMI range when they actually have an above-optimal BF%.

    I struggle with the accuracy of this as well. If I am reading it correctly it is really saying that the average female with a BMI of 20 has a body fat percentage of close to 30% with variations between 20% and 40%. That just does not seem correct.

    My viewing of the graph has female BMI of 20 at between 25 and 35 percent.

    I found this using Google Images search of BMI vs body fat, there are a number of graphs available and you can usually read the papers they came from.
  • samhennings
    samhennings Posts: 441 Member
    kimny72 wrote: »
    BMI was never meant to be conclusive as a singular metric. Saying it falls down as a singular metric doesn't disprove it. That's like saying the front leg on your tripod is useless because it won't hold up your camera on it's own.

    BMI was meant to be a general guideline statistically and then taken into consideration along with other health indicators to get a complete picture on the individual level. You look at BMI, weight, BF %, waist measurement, waist to hip ratio, blood pressure, A1C, heart rate, lung sounds, etc and come to a conclusion. There are situations where one or two of those metrics might not be optimal but the rest are fine so you don't have to worry about it.

    It's also important to remember that "health" is not a yes or no proposition, it's a sliding scale. There are myriad variables that make you more or less likely to get myriad conditions. All the BMI range is trying to do, is get you into a statistically lower risk category. Just like there are lifetime smokers who get to 90 and never get cancer, or people who drunk drive and don't get in an accident, you can live outside the healthy BMI range and be healthy. You just have a statistically higher risk, based on demographic data.

    I'd say if you are above the healthy BMI range, and don't want or think you need to get lower, focus on the other metrics. If the other metrics are also out of line, then you might want to reconsider your perception of health, or you might be fine just consciously accepting the additional risk you are taking on. You get to choose, though I suppose your insurance company might make you pay for that choice.

    i totally agree with that, however several of my doctors and a nurse practitioner doesn't seem to have gotten the memo. all of them strongly believe in BMI as the one and only metric they're concerned with. this was a problem for me when i was a bodybuilder with some fat on me, and is one of the reasons i kept changing doctors.

    my current doctor actually seems to agree with what you just wrote, btw.

    Exactly, and this is my predominant issue with the use of BMI.

    It is not correct/accurate/perfect for everyone, but is very often the only metric used to judge a persons weight/health. In my case it is flawed.

    Could be a geographical divide here, Im in the UK - we dont get regular blood work done, things like that, so BMI is often the only real "test" applied.

    I get the impression that in the States things like blood work are much more common.
  • samhennings
    samhennings Posts: 441 Member
    sijomial wrote: »
    kimny72 wrote: »
    BMI was never meant to be conclusive as a singular metric. Saying it falls down as a singular metric doesn't disprove it. That's like saying the front leg on your tripod is useless because it won't hold up your camera on it's own.

    BMI was meant to be a general guideline statistically and then taken into consideration along with other health indicators to get a complete picture on the individual level. You look at BMI, weight, BF %, waist measurement, waist to hip ratio, blood pressure, A1C, heart rate, lung sounds, etc and come to a conclusion. There are situations where one or two of those metrics might not be optimal but the rest are fine so you don't have to worry about it.

    It's also important to remember that "health" is not a yes or no proposition, it's a sliding scale. There are myriad variables that make you more or less likely to get myriad conditions. All the BMI range is trying to do, is get you into a statistically lower risk category. Just like there are lifetime smokers who get to 90 and never get cancer, or people who drunk drive and don't get in an accident, you can live outside the healthy BMI range and be healthy. You just have a statistically higher risk, based on demographic data.

    I'd say if you are above the healthy BMI range, and don't want or think you need to get lower, focus on the other metrics. If the other metrics are also out of line, then you might want to reconsider your perception of health, or you might be fine just consciously accepting the additional risk you are taking on. You get to choose, though I suppose your insurance company might make you pay for that choice.

    i totally agree with that, however several of my doctors and a nurse practitioner doesn't seem to have gotten the memo. all of them strongly believe in BMI as the one and only metric they're concerned with. this was a problem for me when i was a bodybuilder with some fat on me, and is one of the reasons i kept changing doctors.

    my current doctor actually seems to agree with what you just wrote, btw.

    Exactly, and this is my predominant issue with the use of BMI.

    It is not correct/accurate/perfect for everyone, but is very often the only metric used to judge a persons weight/health. In my case it is flawed.

    Could be a geographical divide here, Im in the UK - we dont get regular blood work done, things like that, so BMI is often the only real "test" applied.

    I get the impression that in the States things like blood work are much more common.

    Disagree with the bolded (I'm in the UK too). Going solely by BMI is contrary to the NHS's own guidelines.

    From the NHS website - "You can use your BMI result as a starting point for further discussion with a GP about your weight and general health."
    Now to me that sounds a very sensible way to use a simple and free tool that gives a reasonable guideline to the majority.

    That Doctors and other medics are of a variable standard isn't unique to the UK.
    That tools are misunderstood and misused is also far too common.

    I can only tell you how I see it used/implemented/spoke of.

    And while that is a very sensible way of looking at it, its not necessarily how its used in the real world.

    Just look on here at the number of people slavishly trying to fit into that BMI range, and stressing about whether they will/wont make it. Or the number of people who are having their doctors take BMI as an absolute and telling them to fit...

    My intent in this thread in the first place was to try and illustrate how it isnt the be all/end all, and is in fact fallible.

    Considering the worry and stress it brings to people I thought it was a pertinent point to make. That was all.

  • kq1981
    kq1981 Posts: 1,098 Member
    sijomial wrote: »
    kimny72 wrote: »
    BMI was never meant to be conclusive as a singular metric. Saying it falls down as a singular metric doesn't disprove it. That's like saying the front leg on your tripod is useless because it won't hold up your camera on it's own.

    BMI was meant to be a general guideline statistically and then taken into consideration along with other health indicators to get a complete picture on the individual level. You look at BMI, weight, BF %, waist measurement, waist to hip ratio, blood pressure, A1C, heart rate, lung sounds, etc and come to a conclusion. There are situations where one or two of those metrics might not be optimal but the rest are fine so you don't have to worry about it.

    It's also important to remember that "health" is not a yes or no proposition, it's a sliding scale. There are myriad variables that make you more or less likely to get myriad conditions. All the BMI range is trying to do, is get you into a statistically lower risk category. Just like there are lifetime smokers who get to 90 and never get cancer, or people who drunk drive and don't get in an accident, you can live outside the healthy BMI range and be healthy. You just have a statistically higher risk, based on demographic data.

    I'd say if you are above the healthy BMI range, and don't want or think you need to get lower, focus on the other metrics. If the other metrics are also out of line, then you might want to reconsider your perception of health, or you might be fine just consciously accepting the additional risk you are taking on. You get to choose, though I suppose your insurance company might make you pay for that choice.

    i totally agree with that, however several of my doctors and a nurse practitioner doesn't seem to have gotten the memo. all of them strongly believe in BMI as the one and only metric they're concerned with. this was a problem for me when i was a bodybuilder with some fat on me, and is one of the reasons i kept changing doctors.

    my current doctor actually seems to agree with what you just wrote, btw.

    Exactly, and this is my predominant issue with the use of BMI.

    It is not correct/accurate/perfect for everyone, but is very often the only metric used to judge a persons weight/health. In my case it is flawed.

    Could be a geographical divide here, Im in the UK - we dont get regular blood work done, things like that, so BMI is often the only real "test" applied.

    I get the impression that in the States things like blood work are much more common.

    Disagree with the bolded (I'm in the UK too). Going solely by BMI is contrary to the NHS's own guidelines.

    From the NHS website - "You can use your BMI result as a starting point for further discussion with a GP about your weight and general health."
    Now to me that sounds a very sensible way to use a simple and free tool that gives a reasonable guideline to the majority.

    That Doctors and other medics are of a variable standard isn't unique to the UK.
    That tools are misunderstood and misused is also far too common.

    I can only tell you how I see it used/implemented/spoke of.

    And while that is a very sensible way of looking at it, its not necessarily how its used in the real world.

    Just look on here at the number of people slavishly trying to fit into that BMI range, and stressing about whether they will/wont make it. Or the number of people who are having their doctors take BMI as an absolute and telling them to fit...

    My intent in this thread in the first place was to try and illustrate how it isnt the be all/end all, and is in fact fallible.

    Considering the worry and stress it brings to people I thought it was a pertinent point to make. That was all.

    I agree with ur post, which was what I was trying to convey through my posts toward BMI. Although many disagreed with the way I felt about the use of the tool and the way I feel about the label Morbid obesity, it's interesting to see people's perceptions.
  • samhennings
    samhennings Posts: 441 Member
    Theoldguy1 wrote: »
    sijomial wrote: »
    kimny72 wrote: »
    BMI was never meant to be conclusive as a singular metric. Saying it falls down as a singular metric doesn't disprove it. That's like saying the front leg on your tripod is useless because it won't hold up your camera on it's own.

    BMI was meant to be a general guideline statistically and then taken into consideration along with other health indicators to get a complete picture on the individual level. You look at BMI, weight, BF %, waist measurement, waist to hip ratio, blood pressure, A1C, heart rate, lung sounds, etc and come to a conclusion. There are situations where one or two of those metrics might not be optimal but the rest are fine so you don't have to worry about it.

    It's also important to remember that "health" is not a yes or no proposition, it's a sliding scale. There are myriad variables that make you more or less likely to get myriad conditions. All the BMI range is trying to do, is get you into a statistically lower risk category. Just like there are lifetime smokers who get to 90 and never get cancer, or people who drunk drive and don't get in an accident, you can live outside the healthy BMI range and be healthy. You just have a statistically higher risk, based on demographic data.

    I'd say if you are above the healthy BMI range, and don't want or think you need to get lower, focus on the other metrics. If the other metrics are also out of line, then you might want to reconsider your perception of health, or you might be fine just consciously accepting the additional risk you are taking on. You get to choose, though I suppose your insurance company might make you pay for that choice.

    i totally agree with that, however several of my doctors and a nurse practitioner doesn't seem to have gotten the memo. all of them strongly believe in BMI as the one and only metric they're concerned with. this was a problem for me when i was a bodybuilder with some fat on me, and is one of the reasons i kept changing doctors.

    my current doctor actually seems to agree with what you just wrote, btw.

    Exactly, and this is my predominant issue with the use of BMI.

    It is not correct/accurate/perfect for everyone, but is very often the only metric used to judge a persons weight/health. In my case it is flawed.

    Could be a geographical divide here, Im in the UK - we dont get regular blood work done, things like that, so BMI is often the only real "test" applied.

    I get the impression that in the States things like blood work are much more common.

    Disagree with the bolded (I'm in the UK too). Going solely by BMI is contrary to the NHS's own guidelines.

    From the NHS website - "You can use your BMI result as a starting point for further discussion with a GP about your weight and general health."
    Now to me that sounds a very sensible way to use a simple and free tool that gives a reasonable guideline to the majority.

    That Doctors and other medics are of a variable standard isn't unique to the UK.
    That tools are misunderstood and misused is also far too common.

    I can only tell you how I see it used/implemented/spoke of.

    And while that is a very sensible way of looking at it, its not necessarily how its used in the real world.

    Just look on here at the number of people slavishly trying to fit into that BMI range, and stressing about whether they will/wont make it. Or the number of people who are having their doctors take BMI as an absolute and telling them to fit...

    My intent in this thread in the first place was to try and illustrate how it isnt the be all/end all, and is in fact fallible.

    Considering the worry and stress it brings to people I thought it was a pertinent point to make. That was all.

    Given that BMI is a fairly good indicator of weigh issues that can have a negative impact on health, maybe it's a good thing they are paying attention to it.

    I am in the overweight category, about 26.5. I have also done resistance training on a consistent basis since I was a teenager. In my annual physical with a company doctor (who rotate so seldom see the same person) they all mention my BMI since it is part of the standard set of things the measure. All of them have told me that my weight is fine due to lower BF%. Not a one has told me to lose weight.



    Sounds like you are under good care then.

    Also sounds like you arent someone overly worrying about BMI or bodyweight, so really my post was never intended for you.

    I have no issue at all with BMI being a metric among many, as part of a whole, and something used as indicative and not absolute.

    I have issue with it being used as THE SINGLE metric, as it often is, because its too fallible for that.
  • Azdak
    Azdak Posts: 8,281 Member

    Theoldguy1 wrote: »
    Azdak wrote: »
    kimny72 wrote: »
    BMI was never meant to be conclusive as a singular metric. Saying it falls down as a singular metric doesn't disprove it. That's like saying the front leg on your tripod is useless because it won't hold up your camera on it's own.

    BMI was meant to be a general guideline statistically and then taken into consideration along with other health indicators to get a complete picture on the individual level. You look at BMI, weight, BF %, waist measurement, waist to hip ratio, blood pressure, A1C, heart rate, lung sounds, etc and come to a conclusion. There are situations where one or two of those metrics might not be optimal but the rest are fine so you don't have to worry about it.

    It's also important to remember that "health" is not a yes or no proposition, it's a sliding scale. There are myriad variables that make you more or less likely to get myriad conditions. All the BMI range is trying to do, is get you into a statistically lower risk category. Just like there are lifetime smokers who get to 90 and never get cancer, or people who drunk drive and don't get in an accident, you can live outside the healthy BMI range and be healthy. You just have a statistically higher risk, based on demographic data.

    I'd say if you are above the healthy BMI range, and don't want or think you need to get lower, focus on the other metrics. If the other metrics are also out of line, then you might want to reconsider your perception of health, or you might be fine just consciously accepting the additional risk you are taking on. You get to choose, though I suppose your insurance company might make you pay for that choice.

    I think whoever invented BMI is stalking this topic and hitting “disagree” with any comment that doesn’t worship BMI.

    Your comment was perfectly reasoned on all fronts. Anyone disagreeing is either a willful troll or someone who is not qualified to sit at the adult table.

    @Azdak given your background in the industry from your observations are there really many people that are obese on the BMI scale and not obese on a measure of bodyfat? I'm guessing a few athletes and maybe another unicorn or 2 but thinking not many given our sedentary society.

    I’ve addressed this before and I try to be scrupulously honest and calibrated in my responses since there are a lot of opinions on this topic.

    First, I don’t have any actual numbers on how many people fall outside the “normal” range of BMI.

    I have my own bias in that I have the education, experience, and tools to measure and interpret actual body fat readings. Unless it’s an outlier, I have a tendency to ignore BMI altogether. That’s not meant to be boastful-it’s actually probably a bad habit on my part.

    I have seen references to 15% or more of the population who don’t fit the standard BMI ranges. My anecdotal observations fit with that. It doesn’t sound like much, but it’s more than you think. And these are “normal” folks—not athletes or bodybuilders, or even recreational lifters.

    I see as many, if not more, people in the low BMI (ie normal BMI/higher body fat) category as in the higher one (high BMI/low body fat)—especially women.

    The numbers skew a little more when people start weight loss programs in our gym. That is because they always have a lifting component. And they don’t realize huge gains in muscle mass, it’s enough that it would be discouraging if all they relied on was the scale or BMI to interpret results.

    That’s as honest as I can be. I’m not as dismissive of BMI as some in my profession because I understand its uses as well as its limitations. But I am wary of the fact that so many medical and health professionals rely on it exclusively and use it as an absolute measure. While not a large number, there are still enough “normal” people who fall outside the range that the average doctor is going to see 10 or 15 per week.
  • kq1981
    kq1981 Posts: 1,098 Member
    edited September 2019
    as a health professional, I agree that a number of 'normal' people fall outside the standard range - particulalry tall sporty young men. Not elite body builders, just general young sporty types.
    Have said this on here many times.

    However by outside the range ,I mean with BMI's of around 27, 28 - not massively outside the range.

    I would be very surprised if any doctors told such men to lose weight or that their weight was an issue.

    On the flip side, I would be very surprised if anyone were concerned abut a petite asian lady having a BMI of just under 18,

    Context and degree matters.

    Absolutely agree. Do you come across many people in practise with a healthy BMI but a lot of visceral fat around their waist? I work in a GP setting in Australia and waist measurements are used more so in risk assessment tools when doing health assessments than BMI. Just interested to see if that is the case for you in your health setting where you're from.
  • paperpudding
    paperpudding Posts: 8,981 Member
    No, not really.

    I don't come across a lot of people with healthy range BMI but high waist measurements.

    On the contrary, I come across many healthy young men with slightly high BMI's but healthy range waist measurements ( the types I mentioned above.)
    But I do a lot of pre employment medicals for industrial jobs - and young fit men are the main demographic of them.

    I also come across many people in other areas of the job who have high BMI and over healthy range waist measurements - have not had one of those yet who I would say that does not accurately show overweight.
  • paperpudding
    paperpudding Posts: 8,981 Member
    That said there is an entire overweight range on the BMI chart between normal and obese. It’s much more likely someone can be healthy and at low health risk in the overweight category than the obese one.

    yes of course.

    Thats what I meant by a matter of degree.

    Obviously the risk for anyone of having a BMI of, say. 28, is different to the risk of one of 45.
  • squiffiegirl
    squiffiegirl Posts: 14 Member
    Interesting that most here advise talking to your doctor. The doctors, nurses, techs, and receptionists at the clinic I go to are all, and I do mean ALL...obese. Morbidly obese.