BMI is a joke

downsizinghoss
downsizinghoss Posts: 1,035 Member
edited October 7 in Health and Weight Loss
So if you plug my height//weight/age in to the BMI calculator it says that my normal weight range should be from about 128-174 pounds.

Well, I went to use a Bod Pod today and found out that my fat free mass (bone/muscle/organs/etc) is 205 pounds.

Pretty safe to say that I am not going to reach 0 body fat and lose 30 pounds of muscle.
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Replies

  • jrgold
    jrgold Posts: 45 Member
    so then what would ur body fat percentage be?
  • downsizinghoss
    downsizinghoss Posts: 1,035 Member
    To fit in the BMI scale my body fat percentage would have to be ZERO. I weigh 205 not counting the fat. No way I could physically reach 174.

    As it is unfortunately I am in the 420's now at 51% body fat. But since I used to be 530 I will take it.. for now!
  • jrgold
    jrgold Posts: 45 Member
    Interesting. i think bmi is just a guideline, body fat percentage matters more. at least you HAVE muscle though already.
  • EricMurano
    EricMurano Posts: 825 Member
    BMI should be used for aggregate - like assessing the health of a population.

    BMI for an individual should really only be used as a starting point and more accurate metrics like the bod pod should be used when you get closer to a 'healthy BMI'.
  • Pebbles536
    Pebbles536 Posts: 199
    Interesting. i think bmi is just a guideline,

    Don't tell my Dr. that. I was 175 (5'6') she said I was OBESE and had to lose 30 pounds. That was 4 years and I could give anything to be 175lbs again. :embarassed: I'm now 280.
  • spazzticaunt
    spazzticaunt Posts: 17
    BMI for me is a tricky thing. I don't completely understand it although I do think that its a fat vs muscle ratio more than anything.

    I was told by someone that you do need some fat but its the "good" fat that you need not the "bad" fat. But I still don't understand what he's actually talking about, but I do know that I think its impossible to have absolutely NO body fat and all muscle.

    its just my opinion
  • spazzticaunt
    spazzticaunt Posts: 17
    Interesting. i think bmi is just a guideline,

    Don't tell my Dr. that. I was 175 (5'6') she said I was OBESE and had to lose 30 pounds. That was 4 years and I could give anything to be 175lbs again. :embarassed: I'm now 280.

    I always bounced between 165 and 180 as a teen and young adult and no doctor of mine told me I was obese just a little over weight which was completely manageable and liveable for them. It wasn't until my hypothyroid kicked in that they started flipping out cause at one point I had gained as much as 18lbs within a 2 week time frame.

    And that was when I was walking 3 miles a day AND walking from one end of the city to the other with no hesitation.
  • gunmetalsunrise
    gunmetalsunrise Posts: 131
    Interesting. i think bmi is just a guideline,

    Don't tell my Dr. that. I was 175 (5'6') she said I was OBESE and had to lose 30 pounds. That was 4 years and I could give anything to be 175lbs again. :embarassed: I'm now 280.

    A lot of doctors still believe things that have long been debunked. Doesn't mean all docs are bad though. Many keep up with latest health science information.
  • kala_rebecca
    kala_rebecca Posts: 51 Member
    I've heard that before, too. I just used it as a guideline to determine my "goal weight", and I'll adjust my healthy weight once I get closer to goal.
  • ninerbuff
    ninerbuff Posts: 48,985 Member
    To fit in the BMI scale my body fat percentage would have to be ZERO. I weigh 205 not counting the fat. No way I could physically reach 174.

    As it is unfortunately I am in the 420's now at 51% body fat. But since I used to be 530 I will take it.. for now!
    Find out what your lean body mass is, then divide it by 20 minus the actual body fat percentage you'd like to be. This will be your goal weight.

    http://www.myfitnesspal.com/topics/show/304029-a-quick-way-to-figure-out-your-ideal-weight?error_user_id=9285851&error_username=ninerbuff&hl=find+your+lean+body+mass+and+divide+that+
  • mshidden
    mshidden Posts: 24 Member
    That is Great Progress, going form 530 to 420, it all about taking it off, don't worries about ideal numbers yet. Your focuses should be about going in the right direction. Set you 12 month goal and shoot for it. Realistically it will take you more then a year to take off what you have put on. I really hope you stick with the program, I really want to talk about your BMI when your 215 lbs. Show me those abs, if you have abs at 215 lb I will give you a $100 bucks. It can been done, and It will be worth every penny. Good luck.
  • Clarecbear82
    Clarecbear82 Posts: 369 Member
    I think bmi is good as a starting point for someone but it isn't the best measure if you are already healthy. It gave me the much needed kick up the bum I needed to make changes in my life. I was completely in denial until my Dr told me I was at the high end of obese so it does have its uses
  • tashaeastland
    tashaeastland Posts: 7 Member
    I don't agree w bmi either...u don't know what those numbers are based of off
  • Tenoreo90
    Tenoreo90 Posts: 329 Member
    As others said, they are definitely guidelines. I'm 5'1, a few years ago I got down to 125, and was TINY TINY...originally when I saw my doctor a year earlier at 135 she told me to aim for 112. o.o
  • Nopedotjpeg
    Nopedotjpeg Posts: 1,805 Member
    Apparently I'm supposed to be between 165-195 pounds. Lol BMI is a crock. Please tell me how people that have a BMI of 30 and a bodyfat % of 5-10 are obese.
  • Russellb97
    Russellb97 Posts: 1,057 Member
    Bad Misleading Information
  • LolaGotThin
    LolaGotThin Posts: 111 Member
    I found this site that uses body types to classify what you should look like/weigh. There is ectomorph, which are naturally skinny, can't easily gain weight; mesomorphs, who can lose weight fairly easily by exercise and a good diet; and endomorphs, who are predisposed to have a lot of body fat and for whom it's very difficult to lose weight. You can fall into two categories, for instance, I display both Mesomorphic and Endomorphic qualities. I haven't actually gotten the tape measure to see where I am (it measures your actual frame) but from what I've read, this is more reliable and accurate than BMI.
    That being said, I'm not an expert. :>
  • heybales
    heybales Posts: 18,842 Member
    BMI for me is a tricky thing. I don't completely understand it although I do think that its a fat vs muscle ratio more than anything.

    I was told by someone that you do need some fat but its the "good" fat that you need not the "bad" fat. But I still don't understand what he's actually talking about, but I do know that I think its impossible to have absolutely NO body fat and all muscle.

    its just my opinion

    You are correct, your body requires some fat around internal organs, other for regulation.
    And if the body goes to low, it will start breaking muscle down for energy to spare the fat. Because if you have gotten to that point the body thinks there is trouble ahead, better hold on to a great energy source, and shut this metabolism down to slow mode.
    Of course, getting to that point is mighty difficult, as most would fool the body into sparing the fat while it actually has plenty to spare.
  • Aviendha_RJ
    Aviendha_RJ Posts: 600 Member
    If you don't mind me asking, what is your height? And what calculator did you use to figure out your BMI?
  • ctalimenti
    ctalimenti Posts: 865 Member
    BMI is accurate for the average person. Most people don't weight train or work out like crazy so aren't going to be lopsided on the muscle side of things.
  • rdzilla
    rdzilla Posts: 113 Member
    As many have said the BMI is a guideline for the average person with the average build. Anyone with some weight (fat, muscle or both) will instantly be overweight or obese. At 308 pounds I weigh a lot and, trust me on this one, it isn't all muscle. At my goal weight of 240 pounds I'm still going to beconsidered obese for a 6'2" male according to BMI calculations. In college we had a true body composition done as part of our athletic program and mine came up as 228 pounds of muscle and I weighed in at 265-270 pounds at the time or ~15% body fat. If I can somehow get to my goal weight it should be the best that I've ever felt and I, nor my Scandanavian genes and bone structure, care what BMI has to say about it.

    "Bad Misleading Information" => LOL
  • kunibob
    kunibob Posts: 608 Member
    Yeah, while my case isn't =as extreme, 0% body fat would still put me in the healthy BMI range...riiiight. :S It is a guideline and not an absolute rule, for sure. You will probably notice a decrease in lean mass as you continue to lose weight (I had a small decrease even with weight training + consuming lots of protein), but I doubt it will be anything near 30 lb worth! % body fat is a FAR better indicator.
  • Allasauna
    Allasauna Posts: 6
    This is just off wikipedia:

    The body mass index (BMI), or Quetelet index, is a heuristic proxy for human body fat based on an individual's weight and height. BMI does not actually measure the percentage of body fat. It was invented between 1830 and 1850 by the Belgian polymath Adolphe Quetelet during the course of developing "social physics".[1] Body mass index is defined as the individual's body weight divided by the square of his or her height. The formulae universally used in medicine produce a unit of measure of kg/m2. BMI can also be determined using a BMI chart,[2] which displays BMI as a function of weight (horizontal axis) and height (vertical axis) using contour lines for different values of BMI or colors for different BMI categories.

    While the formula previously called the Quetelet Index for BMI dates to the 19th century, the new term "body mass index" for the ratio and its popularity date to a paper published in the July edition of 1972 in the Journal of Chronic Diseases by Ancel Keys, which found the BMI to be the best proxy for body fat percentage among ratios of weight and height;[3][4] the interest in measuring body fat being due to obesity becoming a discernible issue in prosperous Western societies. BMI was explicitly cited by Keys as being appropriate for population studies, and inappropriate for individual diagnosis. Nevertheless, due to its simplicity, it came to be widely used for individual diagnosis, despite its inappropriateness.



    It goes on some more but the point is that its not a very accurate way to measure someone's health. Its just a simple guideline. If your BMI comes out high and you do not seem to be very overweight, then an accurate measurement of your percentage of body fat should be taken to determine if and how much weight you could/should lose.
  • shakybabe
    shakybabe Posts: 1,578 Member
    according to wii fit mine should be 22 and I'm 24. something, but body fat scales give a different reading and a different BMR thats higher than what MFP gives me!.. (though it also gives me a different weight too). It's annoying they were the most expensive scales but get no where the same weight on them as my other bathroom scales or wii which are all around the same number.

    As 3 out of 4 are the same I go with the number that's been given by 3 of them! According to the body fat scales though my body fat was consistently going down and lean muscle mass up, when I got them I was loads lighter on them (up to a stone difference some times) now I find I'm getting heavier readings on those and lighter on all the others, it makes no sense!!!
  • manjingirl
    manjingirl Posts: 188 Member
    Firstly congratulations on your weight loss so far. You must be pleased, I know I would be.

    With regard to BMI - you cannot take your current estimate of lean body mass and assume that it will be the same or similar when you lose the desired amount of weight. You will lose some lean mass, even if you eat well, exercise and do all the right things. Your muscles will not need to move so much weight around, your bones won't need to support the weight, you won't have the same blood volume etc.

    BMI is a guide only and is an indication for your risk of developing several weight-related health problems like diabetes, arthritis, heart disease amongst others. BMI is pretty good for most people except very muscular men, and occasionally very very muscular women.
  • EricMurano
    EricMurano Posts: 825 Member
    BMI for me is a tricky thing. I don't completely understand it although I do think that its a fat vs muscle ratio more than anything.

    I was told by someone that you do need some fat but its the "good" fat that you need not the "bad" fat. But I still don't understand what he's actually talking about, but I do know that I think its impossible to have absolutely NO body fat and all muscle.

    its just my opinion

    Your body needs some fat to stay alive. There's two "places" where fat is stored on your body. Subcutaneous fat and visceral fat.

    Subcutaneous fat is the fat under your skin. It's the fat you 'see' in the mirror
    Visceral fat is the fat that's in between your organs.

    You needs ome visceral fat because it cushions your internal organs. If you have very low body fat and you fall over or contort your body in a weird way you might injure your organs.

    Body fat also plays a big part in hormone regulation. Ever hear or women whose periods stop when they get very lean? This is because of this hormone thing.

    Women need more fat on their bodies than men do. That being said women at their healthy body fat percentage will look really slim so don't get so caught up on the number.
  • EricMurano
    EricMurano Posts: 825 Member
    Firstly congratulations on your weight loss so far. You must be pleased, I know I would be.

    With regard to BMI - you cannot take your current estimate of lean body mass and assume that it will be the same or similar when you lose the desired amount of weight. You will lose some lean mass, even if you eat well, exercise and do all the right things. Your muscles will not need to move so much weight around, your bones won't need to support the weight, you won't have the same blood volume etc.

    BMI is a guide only and is an indication for your risk of developing several weight-related health problems like diabetes, arthritis, heart disease amongst others. BMI is pretty good for most people except very muscular men, and occasionally very very muscular women.

    Very good points
  • downsizinghoss
    downsizinghoss Posts: 1,035 Member
    I am 5'10''. It is a standard set of tables (which is why it isn't always very good). One place you can check it is under the tools tab on this site.
  • ElizabethRoad
    ElizabethRoad Posts: 5,138 Member
    I don't know why everyone complains about BMI being inaccurate. It was never meant to be used on individuals. It's like saying that your screwdriver is a joke because it doesn't hammer very well.
  • Acg67
    Acg67 Posts: 12,142 Member
    To fit in the BMI scale my body fat percentage would have to be ZERO. I weigh 205 not counting the fat. No way I could physically reach 174.

    As it is unfortunately I am in the 420's now at 51% body fat. But since I used to be 530 I will take it.. for now!

    You are making the assumption that you will have no muscle loss while dieting, which is an incorrect assumption
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