Does bmi really matters?

Kyaface
Kyaface Posts: 17 Member
edited December 1 in Fitness and Exercise
I'm just wondering because some people look good even though their bmi says other wise.
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Replies

  • MinimalistShoeAddict
    MinimalistShoeAddict Posts: 1,946 Member
    Looking good and being healthy are not the same thing. Of course there are some people with overweight BMIs
    that are healthier than many people with a BMI in the ideal range. However the risk factor for many diseases (diabetes, heart disease, etc) is much higher for those who are significantly overweight.
  • Machka9
    Machka9 Posts: 25,698 Member
    My BMI matters to me and works for me.

    When I have slipped into the overweight range (3 times in my life), I have known I was overweight, I felt overweight, I looked overweight, and I was inspired to lose the weight ASAP.

    I'm most comfortable in the lower half of my normal BMI range.
  • ninerbuff
    ninerbuff Posts: 49,029 Member
    edited May 2016
    BMI, while deceiving for actual health status, won't go away because it's the scale of how many health insurance/life insurance companies determine the premiums. My insurance is higher than someone of the same age and height but who's 50lbs less than me because I tip towards the obese side of BMI. And of course my physique shows that.....................

    A.C.E. Certified Personal and Group Fitness Trainer
    IDEA Fitness member
    Kickboxing Certified Instructor
    Been in fitness for 30 years and have studied kinesiology and nutrition

    9285851.png
  • cgvet37
    cgvet37 Posts: 1,189 Member
    The BMI is a broken scale. It literally should removed from history.

    According to Navy standards you can be 300lbs out of shape, health issues out the butt..... but if you lift and your neck is so many inches, and your waist is x (can't remember the exact numbers) then the person who lifts is considered obese while the 300lber is applicable to the Navy.

    Anyhow, I'm considered obese according to the BMI.... I guess my abs are made of jelly.

    I went through basic with a guy that I would consider obese. However, he had a thick neck and large wrists.
  • Sabine_Stroehm
    Sabine_Stroehm Posts: 19,263 Member
    It's one tool. And it's a way to compare folks across the spectrum, easily.
    There aren't really any EASY tools to do that with. Docs aren't going to do body fat testing on everyone who comes in their office.
    That said, yes, those who seriously lift sometimes end up with misleading numbers.
    For the average woman, or average man, it can provide some useful information, just as BP, resting heart rate etc. can.
  • LazSommer
    LazSommer Posts: 1,851 Member
    ninerbuff wrote: »
    BMI, while deceiving for actual health status, won't go away because it's the scale of how many health insurance/life insurance companies determine the premiums. My insurance is higher than someone of the same age and height but who's 50lbs less than me because I tip towards the obese side of BMI. And of course my physique shows that.....................

    A.C.E. Certified Personal and Group Fitness Trainer
    IDEA Fitness member
    Kickboxing Certified Instructor
    Been in fitness for 30 years and have studied kinesiology and nutrition

    9285851.png

    All those donuts bro.
  • JeromeBarry1
    JeromeBarry1 Posts: 10,179 Member
    The BMI scale was created during a famine in France around 1880, just before Marie Antionette responded to the cries of the peasantry for bread by saying "Let them eat cake." (apocryphal). We can discredit lies about a glam babe but we can't discredit health charts created by observing people during a famine.
  • paperpudding
    paperpudding Posts: 9,304 Member
    The BMI is a broken scale. It literally should removed from history.

    According to Navy standards you can be 300lbs out of shape, health issues out the butt..... but if you lift and your neck is so many inches, and your waist is x (can't remember the exact numbers) then the person who lifts is considered obese while the 300lber is applicable to the Navy.

    Anyhow, I'm considered obese according to the BMI.... I guess my abs are made of jelly.

    Or you have enough abs to put you in the outlier group who have a high BMI due to muscle mass.
    But that doesn't make BMI, as a guide, a useless guide.

    BMI is a guide to be used in conjunction with the clinical picture ie with seeing the persons body.
    When seeing the persons body it is obvious whether they have a BMI of 40 because they have muscle mass or because they are obese.

    I know when I had a BMI of 28, it wasn't because I had high level of muscle - it was because I was overweight.

    BMI is a useful tool for most people - outliers do not change that.
  • robininfl
    robininfl Posts: 1,137 Member
    BMI matters and can be a good general indicator, especially for females since they can't put on enough muscle mass naturally to be classed as obese. Slightly over normal is fine for some, and slightly under normal is fine for someone very small framed.

    Males are a little different, they can creep up a little higher on the BMI scale due to muscle if they train, but I believe that those who can reach a weight high enough to be considered obese (over 30 BMI) naturally and purely from muscle are outliers and a scale of averages does not apply to them. This does not discredit BMI as a good general gauge, it only makes them an exception to the rule.

    In general, it's just one of the tools that give you a more complete general idea. So if you consider BMI, body fat and waist circumference you get a better idea of your overall health. I think a new "overweight" and "obese" BMI cut off points should be designed specifically for athletes, but until then common sense is good enough.

    Yes, the way I understand it is that BMI is more likely to underestimate obesity, than to overestimate it. It's more usual to have too much bodyfat and a normal BMI, than to have a healthy amount of bodyfat and an obese BMI.

  • French_Peasant
    French_Peasant Posts: 1,639 Member
    The BMI scale was created during a famine in France around 1880, just before Marie Antionette responded to the cries of the peasantry for bread by saying "Let them eat cake." (apocryphal). We can discredit lies about a glam babe but we can't discredit health charts created by observing people during a famine.

    She got her head chopped in 1793 (sorry, I am a complete history geek) but your comment piqued my interest; the body measurement concept was developed by Quetelet in the mid-1800s, but popularized in its current form by Ancel Keys, the kitten-bag behind the low-fat shenanigans.
  • hekla90
    hekla90 Posts: 595 Member
    edited May 2016
    Very few people are true outliers in BMI- not many are walking around with an obese bmi due to muscle, it's much more likely to underestimate body fat than overestimate. Also goes the other way too: I've had a hard time being taken seriously in the past with an underweight bmi of 15.8 because I looked healthy. It's one measurement tool, it's not the end all be all but I generally think it holds reasonably fine for most people.
  • scorpio516
    scorpio516 Posts: 955 Member
    BMI is incredibly useful, for it's intended purpose. As a statistic of a population. Be that population of 5 million pre-revolutionary French, 50 million Met Life Insurance subscribers, or 300 million Americans.
    You can get height and weight from a population fairly easily. Imagine how much effort it would be to get accurate BF% measurements from millions and millions of people...
  • Snipsa
    Snipsa Posts: 172 Member
    I agree with the consensus that BMI is a fairly accurate representation of a person's general health/level of obesity.

    I know that when my BMI was 31 it was because I was overweight/obese. And although my BMI is currently 25.2 (sooooo close), when I look in the mirror I know I am still overweight and have another 10 to 12 Kg to go before I would consider myself at a "good" weight for my height. Muscle mass plays it's part, but it is a good indicator for those not built like Terminator...
  • LKArgh
    LKArgh Posts: 5,178 Member
    In general, yes. Perhaps for a small percentage of people who are very athletic, it might give a false positive for being oveweight, but few "common" people are outliers. While I have seen many people claim that BMI does not apply to them because while theoretically obese, they are in fact fine, I have very rarely seen this to be true. It usually is more IMHO a biased perception about what healthy weight looks like than the person actually being as slim as he/she thinks. It is usually overweight people who claim they look and are at a healthy weight and BMI is "broken". Most of them, they might be thinner than they used to be or fitter than they used to be, or thinner and fitter than their friends and relatives, but this does not automatically mean they aren't still overweight.
  • LKArgh
    LKArgh Posts: 5,178 Member
    http://www.hsph.harvard.edu/obesity-prevention-source/obesity-definition/obesity-definition-full-story/

    "As obesity rates have soared, people’s perceptions of what constitutes a healthy weight appear to have shifted: A recent U.S. study comparing weight perception surveys from the late 1980s to the early 2000s found that in the early 2000s, people were more likely to consider their own weight “about right” instead of “overweight.” (24) Some of these people were truly at a healthy weight, but many of them were not."
  • wilsoncl6
    wilsoncl6 Posts: 1,280 Member
    I wouldn't say that BMI is a good indicator for health anymore for varying reasons:

    1. The advent of gyms and their usage, along with strength training, which has increased in various countries.
    2. The diets of different Western cultures have changed. Meat is more plentiful and eaten on a regular basis much more than it has been in the past. More protein in a diet, means more muscle mass if combined with regular exercise.

    Granted, the perception of what is considered a healthy weight has changed over time, but so has average heights and average builds.

    My BMI for my height would have me at 185 lbs for overweight and 220 as obese. I was at 185 for a long time and thought I looked pretty darn skinny. At my current weight I'd be considered overweight at 15% bodyfat.
  • Packerjohn
    Packerjohn Posts: 4,855 Member
    wilsoncl6 wrote: »
    I wouldn't say that BMI is a good indicator for health anymore for varying reasons:

    1. The advent of gyms and their usage, along with strength training, which has increased in various countries.
    2. The diets of different Western cultures have changed. Meat is more plentiful and eaten on a regular basis much more than it has been in the past. More protein in a diet, means more muscle mass if combined with regular exercise.

    Granted, the perception of what is considered a healthy weight has changed over time, but so has average heights and average builds.

    My BMI for my height would have me at 185 lbs for overweight and 220 as obese. I was at 185 for a long time and thought I looked pretty darn skinny. At my current weight I'd be considered overweight at 15% bodyfat.

    True statements if people used gyms. Only about 15% of the population reports they do resistance work so the general population isn't getting more muscular


  • wilsoncl6
    wilsoncl6 Posts: 1,280 Member
    Packerjohn wrote: »
    wilsoncl6 wrote: »
    I wouldn't say that BMI is a good indicator for health anymore for varying reasons:

    1. The advent of gyms and their usage, along with strength training, which has increased in various countries.
    2. The diets of different Western cultures have changed. Meat is more plentiful and eaten on a regular basis much more than it has been in the past. More protein in a diet, means more muscle mass if combined with regular exercise.

    Granted, the perception of what is considered a healthy weight has changed over time, but so has average heights and average builds.

    My BMI for my height would have me at 185 lbs for overweight and 220 as obese. I was at 185 for a long time and thought I looked pretty darn skinny. At my current weight I'd be considered overweight at 15% bodyfat.

    True statements if people used gyms. Only about 15% of the population reports they do resistance work so the general population isn't getting more muscular


    That may be true about gyms, but the statistics show that there has been a gradual increase in the US of those people that report doing some level of strength training (69.6% in 1999 to 74.3% in 2002). True, many people may not use a gym but that doesn't mean a good portion of people (in the US at least) do some form of strength training at least 2 times a week. Strength training is something that is designed to either build muscle or overall strength, and is anything that isn't particularly focused on cardiovascular work.
  • wilsoncl6
    wilsoncl6 Posts: 1,280 Member
    Actually, I was looking at old data. CDC data puts the number of US population doing the recommended allowance of strength training at 20.8% but has generally increased over time since 1997.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    Kyaface wrote: »
    I'm just wondering because some people look good even though their bmi says other wise.

    BMI is a reasonable indicator of whether one is of a healthy weight for most people. That said, it isn't the best measure of overall health. I know people who are at a "healthy BMI" but aren't in the least healthy people. Myself, I'm considered just slightly overweight by BMI standards, but I'm at about 12% BF. At the very high end of BMI for my stats, I'd be incredibly lean.
  • itsbasschick
    itsbasschick Posts: 1,584 Member
    BMI is an indicator for those who are neither unusually unmuscular nor unusually muscular. i've been 170 pounds twice, once while i was strength training like mad, very muscled for a woman, had normal blood pressure and blood sugar and felt great. the second time was after injuries and long term issues when i was unusually low in lean body mass and had high blood pressure and high blood sugar. if you believe BMI, both times i was unhealthily overweight.
    The BMI scale was created during a famine in France around 1880, just before Marie Antionette responded to the cries of the peasantry for bread by saying "Let them eat cake." (apocryphal). We can discredit lies about a glam babe but we can't discredit health charts created by observing people during a famine.

    marie antoinette died in the late 1700s. just saying.

  • scorpio516
    scorpio516 Posts: 955 Member
    marie antoinette died in the late 1700s. just saying.

    LOL. But it was created by a Belgian between 1850 and 1870, which at the time was part of the Netherlands. The creator was big on bringing statistics into social sciences.
  • LKArgh
    LKArgh Posts: 5,178 Member
    wilsoncl6 wrote: »
    I wouldn't say that BMI is a good indicator for health anymore for varying reasons:

    1. The advent of gyms and their usage, along with strength training, which has increased in various countries.
    2. The diets of different Western cultures have changed. Meat is more plentiful and eaten on a regular basis much more than it has been in the past. More protein in a diet, means more muscle mass if combined with regular exercise.

    Granted, the perception of what is considered a healthy weight has changed over time, but so has average heights and average builds.

    My BMI for my height would have me at 185 lbs for overweight and 220 as obese. I was at 185 for a long time and thought I looked pretty darn skinny. At my current weight I'd be considered overweight at 15% bodyfat.

    I would expect the exact opposite to be true for western societies: more food, especially calorie dense convenience food, little to no walking, less physical labour, lots of hours spent at desk jobs followed by hours in front of a screen. None of this can be compensated by a few hours spent every week at the gym.
  • saphin
    saphin Posts: 246 Member



    [/quote]

    That may be true about gyms, but the statistics show that there has been a gradual increase in the US of those people that report doing some level of strength training (69.6% in 1999 to 74.3% in 2002). True, many people may not use a gym but that doesn't mean a good portion of people (in the US at least) do some form of strength training at least 2 times a week. Strength training is something that is designed to either build muscle or overall strength, and is anything that isn't particularly focused on cardiovascular work.[/quote]

    Sadly your logic is flawed for at least three reasons:

    1. Owning equipment or gym membership does not mean the you are weight training. It only means you have the means to weight train.

    2. As a general rule, more people will claim to exercise than actually do exercise. Self reported data is therefore of little use in a serious analysis. Even those that do exercise will tend to overreport time and overestimate intensity of the exercise. (We've all seen this people that turn up, do a 10 minute cardio warmup, faff with the weights aimlessly for a few minutes then spend the next 30 minutes on selfies or playing on their phones)

    3. Of people that do weight train, it is still only the very small minority that build sufficient muscle mass to go into the overweight or obese weight categories while at a low body fat.

    Is the BMI therefore useless?

    I would have to say no; but only to sort out the acceptable weight people and pass those falling below and above acceptable for further screening
  • Sabine_Stroehm
    Sabine_Stroehm Posts: 19,263 Member
    wilsoncl6 wrote: »
    I wouldn't say that BMI is a good indicator for health anymore for varying reasons:

    1. The advent of gyms and their usage, along with strength training, which has increased in various countries.
    2. The diets of different Western cultures have changed. Meat is more plentiful and eaten on a regular basis much more than it has been in the past. More protein in a diet, means more muscle mass if combined with regular exercise.

    Granted, the perception of what is considered a healthy weight has changed over time, but so has average heights and average builds.

    My BMI for my height would have me at 185 lbs for overweight and 220 as obese. I was at 185 for a long time and thought I looked pretty darn skinny. At my current weight I'd be considered overweight at 15% bodyfat.

    This suggests that folks are more likely to be outliers due to muscle now than in the past. I doubt that's true.
  • paperpudding
    paperpudding Posts: 9,304 Member
    I think it is highly unlikely that more people are so muscular now than previously such that BMI statistics are getting skewed.

    Sure, there are more gyms but only a minority of the population use them regularly but on the other hand far less people do incidental exercise than previously - ie people don't walk, they use transport, they don't have physical jobs or do physical work around the house, now that there are so many labour saving machines.
  • auddii
    auddii Posts: 15,357 Member
    I think it is highly unlikely that more people are so muscular now than previously such that BMI statistics are getting skewed.

    Sure, there are more gyms but only a minority of the population use them regularly but on the other hand far less people do incidental exercise than previously - ie people don't walk, they use transport, they don't have physical jobs or do physical work around the house, now that there are so many labour saving machines.

    Agreed. I'd say the BMI being accurate across the population are still a bell curve with it not being effective for a few individuals at either tail end. For the most part, I'd say the BMI could be considered a good indicator for health (more effective when combined with additional stats like body fat %).

    That said, lots of people who are unhealthy or overweight can look good; those two factors don't necessarily related to one another.
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