Ignoring BMI

QueenBishOTUniverse
QueenBishOTUniverse Posts: 14,121 Member
in Fitness and Exercise
Ok, I'll admit, I've never liked BMI. I've always been suspicious that it doesn't really apply to me, but everything I read says that BMI should be used unless you're some kind of extreme athlete, which I definitely am not. HOWEVER, I was running some calculations in my head, and I really think I'm right about this, but I'm no fitness expert so I'm putting my thinking out there. Let me know if there's something I'm missing. Also, what are your thoughts on BMI?

My stats: 5'8" 195lbs, 35% body fat, want to lose 30lbs.

Here's why I think BMI is a crock, if I lose 30 lbs, down to 165, I'm overweight according to BMI, just barely (164 is the max) but still. But wait, if I lose 30 lbs, assuming I'm lifting and maintaing LBM, then that should be fat yes? So my body fat % should be 20%, definitely NOT overweight. I know what I look like at 165 lbs, and I don't look over weight.

Lets take the thought experiment further, drop me down to 15% body fat, that would be 156 lbs. So that means I have an 8 lb margin of error between 15% body fat, and over weight.... huh? I might, MIGHT be able to get down to 156 lbs, I haven't been that weight since college, when I was playing lacrosse and training 3-4 hours a day but sure, it could happen, but I'm supposed to believe that 176 lbs (25% body fat) is over weight for me and unhealthy. I just don't see it.

Anyways, just wondering if I'm missing something here, or if I should stick with my usual premise that as long as I stay under 175 lbs at least health wise, I'm good. I've never been able to get a doctor to give me a strait answer to this question, and I have asked.
«1

Replies

  • littlewhittles
    littlewhittles Posts: 402 Member
    I think body fat % is a better indicator, and BMI is a rough set of numbers for people to go by. Some people might weigh the same, but not have the same lean muscle mass, and actually BE more overweight. I think, if you reliably know your BF% that you can get around the BMI thing.

    How did you determine your BF%? I'm just curious, as I'd like to, but don't have a reliable way to test it.
  • QueenBishOTUniverse
    QueenBishOTUniverse Posts: 14,121 Member
    Just based on measurements, I'm estimated anywhere from 31% to 40%. Based on an electric scale I'm consistently 35%. I had caliper measurements taken many years ago, but I have no idea what they were. Based on eyeballing (I've looked it up, it's a valid method) I'd say 30-35%. So I'm fairly comfortable going with 35%, even if I'm off a point or two, the numbers don't change enough to change my basic premise.
  • grimendale
    grimendale Posts: 2,153 Member
    BMI is more intended as a population measure than as an individual measure. According to BMI, I'm overweight. According to body fat, I'm in the fit range. I've never paid any attention to BMI and never will.
  • DawnieB1977
    DawnieB1977 Posts: 4,248 Member
    I am just barely in the healthy BMI category - 5'6, 154lbs. However my body fat is around 28% which at age 35 is perfectly healthy (although I'd like to get down to 25%) and I wear a UK size 10/12 (US 6/8).

    Years ago I was 147lbs but the same size as now. Back then I just did cardio, so I guess my few extra lbs now could be because I do a lot more strength training. Or it could just be my mummy tummy lol which I did not have pre kids!

    My personal trainer has actually told me I don't need to drop any more weight or I'll start to look gaunt, although I would like to lose a little bit.
  • Canderson58054
    Canderson58054 Posts: 132 Member
    I found this article interesting...
    http://sizeandsubstance.com/2011/11/28/body-mass-index-bmi-where-it-came-from-and-what-its-good-for/

    Crazy that the BMI system was started that long ago!! Times have changed, maybe that system of measuring and judging people should too.
  • coolraul07
    coolraul07 Posts: 1,606 Member
    I pay attention just for insurance purposes, etc. My goal weight (240#) was chosen because at 6'4" my obese/overweight boundary is 246# and I want 6# of wiggle room for fluctuations. I will use strength training to get my BF% down (I estimate 25-29% now) and looks better, but I want to officially stay outta obese territory. My normal/overweight boundary is #204; the last time I was that light I was 17 years old and 4.5" shorter. Looking back on those pics, I was 'skinny fat' and didn't like the way I look. I could imagine how sickly I'd look at that weight now with my height. It wouldn't look right on my frame so IDGAF what the BMI charts say, I ain't doing it!
  • casy84
    casy84 Posts: 290 Member
    How is it that BMI is ignored/dismissed only by overweight people?
    If an underweight would happen to say something like this you would all send him/her to the doctor regardless of bone structure or eating habbits.
  • DawnieB1977
    DawnieB1977 Posts: 4,248 Member
    How is it that BMI is ignored/dismissed only by overweight people?
    If an underweight would happen to say something like this you would all send him/her to the doctor regardless of bone structure or eating habbits.

    My personal trainer thinks BMI is a load of rubbish!

    I am a healthy BMI and I don't think it's the best way of deciding if you're healthy or not. Sure, it's better to be within a healthy BMI range.

    I'm sure some underweight people are perfectly healthy too, although to be under a BMI of 18 you probably have to be pretty small.
  • JesterMFP
    JesterMFP Posts: 3,596 Member
    I think BMI is a blunt tool, and it's more suited for measuring populations rather than individuals.

    However, for individuals, I think it's a good general indicator, especially for people who don't have a way of easily/accurately measuring body fat %. I think the people for whom it is less relevant are those that have a higher percentage of lean mass. Someone can easily be in the "overweight" BMI range, but have a healthy body fat %, and they are likely to have a lot of lean mass.

    For people who are not that active and have average levels of lean mass, BMI is, imo, more relevant. Especially for people who are obese, it gives them a good general idea of where to aim for. I also think it's more relevant when people get towards the lower end. I've seen lots of people who are "overweight" but probably perfectly healthy because of their body fat %. I think that most people who are "underweight" according to the BMI would actually be healthier if they gained some weight.
  • SpleenThief
    SpleenThief Posts: 293 Member
    the most common misconception about BMI is that it indicates obesity or overweightness.

    It indicates you're AT RISK for these. Most people point to the 6'1" linebacker weighing in at 310 pounds. BMI indicates he's obese but he's got 11% body fat. They'll point to this guy and say BMI is bunk.

    but it's not

    His BMI indicates he's at risk for being obese and he should look into the situation with his doctor to find out more.

    Use it as a guideline, take into account other things like %body fat, etc., aerobic conditioning, flexibility and get a good picture of your total health, but don't ignore it and don't discount it.
  • rachseby
    rachseby Posts: 285 Member
    I'm with OP. When I was 145-150 I was "overweight" (I'm 5'3"). Which made me think I was fat and afraid to step on the scale! If I manage to get back into that range, bmi can kiss my overweight butt :)
  • cardiothief
    cardiothief Posts: 8
    BMI is BS
    According to that, I should be between 64-79 kg.
    When I was 78kg I looked sick. My face looked like it was sucked in and my hip bones were sticking out...
    I had almost no body fat and loosing more would just have been unhealthy.
    I have a big build... broad shoulders etc. used to be a rugby player in my younger years...

    Weighing in at 83-85 was perfect for me. 10kg over weight according to my BMI...
    I go on what I feel not what some charts tells me.
  • QueenBishOTUniverse
    QueenBishOTUniverse Posts: 14,121 Member
    Thanks for all the great posts! This was basically what I think as well, but like I said, I could be missing something. As for overweight people wanting to ignore BMI, I understand what you're getting at. That's honestly why I brought up the question, because I thought maybe I was doing that. On the other hand I know what I look like at 165, I wear a size 6-8 long. My SKELETON wouldn't fit in anything smaller than a size 6. I also know when I was in high school my doctor specifically told me to NEVER try to go below 145 because I was much stronger than most people my size and anything below that would be too skinny. My shoulders got a lot bigger and my upper body strength shot up in college, so I really think 156 is my minimum now. Maybe I'm wrong, but when I ask doctors now if my weight is ok when I'm at 170ish, all I get is a bunch of mumbling....
  • JamieM8168
    JamieM8168 Posts: 248 Member
    I was just thinking this the other day! I'm 5' 8 and 162-165 depending on the day, and I looked at my BMI and immediatily thought "really, wtf?" after all my hard work, starting at 250, I'm just now reaching a heathy level of BMI.
    I don't think I can lose that much more weight to be 'average healthy' I'd look nuts at like 135-140.

    I'm just still going to aim for the 155 I had originally planned despite those charts
  • bokodasu
    bokodasu Posts: 629 Member
    Bodyfat is a much better measure, but you will lose *some* LBM if you lose weight. It's not all muscle - it's everything that's in your body that isn't fat. So you won't need as much blood sloshing around or water to fill up your cells or whatever. And probably some muscle will get lost too, that's just the way it goes.

    You kind of just have to see when you get there - if you can be 20% BF at 165 lbs, then yeah, it would be silly to try to go under that, unless your insurance gives you a discount for BMI and then losing the extra pound would be worth the $$.
  • xampx
    xampx Posts: 323 Member
    I agree BMI is crap. I have lost over 50lbs, BMI says I am still obese. To get to a normal BMI I need to lose another 50lbs.

    Every person I have mentioned this to has said no way, you will look hideous if you lose another 50lbs. So I plan to lose at most, another 30lbs which will put me right in the middle over the overweight category.

    I would be much happier with a happy BF% than a 'normal' BMI
  • bumblebums
    bumblebums Posts: 2,181 Member
    How is it that BMI is ignored/dismissed only by overweight people?
    If an underweight would happen to say something like this you would all send him/her to the doctor regardless of bone structure or eating habbits.

    Because BMI is problematic for muscular people who are placed in the overweight range even if they are not carrying much fat. I am not saying it applies to OP necessarily. The standard BMI formula also applies a linear metric to people of various heights, but they do not carry extra weight in the same way:

    http://www.telegraph.co.uk/health/healthnews/9816596/Interactive-calculator-do-you-win-or-lose-with-the-new-BMI.html
    According to Mr Trefethen, the current formula to calculate the score (weight/height2) is incorrect because "it divides the weight by too large a number for short people, and too small a number for tall people. So short people are misled into thinking they are thinner than they are, and tall people are misled into thinking they are fatter than they are."

    Anyway, as others said, BMI is just one of several ways of assessing whether you are at a healthy weight--useful as a starting point, but not something you should rely on exclusively.
  • lilbearzmom
    lilbearzmom Posts: 600 Member
    Um yeah. Take a look at my profile picture. I am still considered obese according to BMI. I am just a couple pounds shy of overweight, but still. My plan is to get down to 160 (still considered overweight by about 11 lbs) and reevaluate. I am thinking I will switch to maintenance and focus on body fat % at that point. My doctor agrees to all of this as well.
  • cwolfman13
    cwolfman13 Posts: 41,865 Member
    Your BF% is far more indicative of your health. I'm no extreme athlete...body builder...shredded...ripped...whatever. I have some decent muscle 'cuz I workout and I train...according to BMI I'm overweight...but I'm at a completely healthy BF% and all of my blood work, etc reflects that. I would think the only thing you might have to concern yourself with is that if you put on a ton of muscle (and thus were overweight by BMI standards) that might be hard on your joints...but I'm nowhere near that. I'm 5'10" and 180 Lbs at 20% BF.
  • aliciaje
    aliciaje Posts: 83
    It is truly unfortunate that doctors and insurance companies apply BMI to an individual then make judgments on ones health purely based on it. It is also unfortunate when people say that anyone who is out of the healthy range and still thinks they are at a healthy weight is in denial.

    I am a "special snowflake" or whatever those rude people want to call it. I have been out of the "healthy" range my whole life. I went to get a BodyPod done a couple weeks ago because I want to know why I am so darn heavy. The results were pretty eye-opening. I am currently at 23.4% BF and weight 163lbs and LEAN body mass of 125.5lbs (aka everything else in your body excluding fat). I am 5'4 making my BMI 28. In order for me to get down to the TOP of the healthy range (145lbs) and maintaining my lean body mass, I would have to be at 13.7%BF. I am NOT interested in losing lean body mass OR getting down to 13.7% BF, so I guess I will just have to accept I will always be in the overweight category.
  • greatwestescape
    greatwestescape Posts: 49
    +1
    I think body fat % is a better indicator, and BMI is a rough set of numbers for people to go by. Some people might weigh the same, but not have the same lean muscle mass, and actually BE more overweight. I think, if you reliably know your BF% that you can get around the BMI thing.

    How did you determine your BF%? I'm just curious, as I'd like to, but don't have a reliable way to test it.
  • ksuh999
    ksuh999 Posts: 543 Member
    Just what is "Lean Mass"??

    http://examine.com/topics/Lean+Mass/

    Yeah so hey when you shrink you also lose water, which is counted in lean mass.

    BMI should be used in conjunction with your BF% and waist size. Waist size especially is a very good indicator of future health problems.

    Insurance companies use mortality rates to calculate life insurance premiums, among other things.
  • sukatx
    sukatx Posts: 103
    I think it's a personal choice based on your goals. For me, I take my body fat % and my body muscle % more seriously than my BMI. That's because I have skin literally hanging off my body from being pregnant and obese at the same time. That skin comes on the scale with me and brings my BMI up showing that I'm overweight, even though my body fat is 24% and my muscle is 34%.
  • QueenBishOTUniverse
    QueenBishOTUniverse Posts: 14,121 Member
    Yea, that's probably the other reason I've always sort of ignored BMI, because I'll use the online calculator and it will say "you're over weight", but then, as soon as I input my waist and hip measurements the calculator backtracks and says "oh never mind, you're perfectly healthy at 175". I'm at the upper range at 175, and I prefer how I look at 165, but I get really annoyed that insurance companies and other organizations will just look at my height and weight and assume I'm over weight. I do a lot of field work and when I apply for different jobs it just gets really obnoxious having to constantly go back and convince the selection people that, no really, I'm in good shape and CAN meet your physical requirements (not right now obviously).
  • PriceK01
    PriceK01 Posts: 834 Member
    I've never payed too much attention to BMI. It's a general tool, based on averages. I'm 5'10" and 126 pounds. This gives me a BMI of 18.1 which is considered underweight. My BF% is still 19, using an average between Covert Bailey and USN Circumference methods. At 160lbs, my doctor told me I needed to lose about 30lbs. Everyone is different, there is no one-size-fits-all method for determining a healthy weight.
  • agdyl
    agdyl Posts: 246 Member
    I'm currently around 175 and 5'8" and don't feel like I need to our should lose much more weight. Maybe 5lbs, but I look and feel pretty fit right now. I've always exercised a lot. But even when I was up in the 190's, I'd mention to my doctor that I'd like to lose weight and they'd look at me and ask "Why? If you want to for cosmetic reasons, that's okay, but you don't need to to be healthy" I have broad shoulders, muscular arms and legs and wide hips but a smaller waist and I think I just hold a lot more weight with my build than someone with a smaller frame. Apparently the average adult woman has a biacromial width (acromial arch on one shoulder to the other) of 14". Mine is 17". (so not counting the delt muscles outside the bone structure). Needless to say, I can hug some of my friends and feel like I engulf them. But no matter what kind of diet I go on, I'm not going to end up with narrow shoulders or hips (my iliac crests are also several inches wider than average) and therefore I would basically have to weigh more than the "average" healthy woman.

    I've been told the waist to hip ratio is a better indicator for health - for that women are ideally less that .75 (others say .8), and I'm at .69, so I'm fine. And even with the overall waist circumference, they recommend less than 31.5" for women and I'm at 28.5. So at least according to those measurements, my big butt isn't hurting me too much. :)

    http://www.whyiexercise.com/waist-circumference.html
    http://www.bmi-calculator.net/waist-to-hip-ratio-calculator/waist-to-hip-ratio-chart.php

    There was only once in my adult life that I've been in the "healthy BMI range" (by like 1 lb) and people told me I was getting too thin. So basically - I've decided to quit worrying about BMI. I don't think it's the most reasonable thing for me to go by.
  • KiltFuPanda
    KiltFuPanda Posts: 574 Member
    BMI is a four letter word in my book.

    I'm an amateur strength competitor - I train maybe 2, 3 times a week. That mostly involves heavy lifting, but I work in some conditioning (mostly tractor tire flips). I'm not ripped at all - I'm just large.

    My BMI is 46. Seriously. 6'3", 360 lbs. I do not deny that I'm overweight, and that I can lose some size. But BMI claims that to be "normal" I have to drop 160 lbs - I'm considered "Class III Obese". And I'm going to call BULL$#!% on that one.

    I have been calipered as around 25% bodyfat. That's 90 lbs of fat, 270 lbs of lean weight. I could stand to get down to 300, as I accept that I may lose some muscle in the process.
  • lsmsrbls
    lsmsrbls Posts: 232 Member
    I think that BMI has marginal utility for large populations and almost no utility on the individual level.

    My BMI is 36 and my body fat percentage is 28%. lol.
  • honeysprinkles
    honeysprinkles Posts: 1,757 Member
    BMI is more intended as a population measure than as an individual measure. According to BMI, I'm overweight. According to body fat, I'm in the fit range. I've never paid any attention to BMI and never will.
    this.

    I plan on losing 10 more pounds (hopefully it will mostly be fat, I'm trying to hold on to my muscle mass) and that will put me right on the border of healthy and underweight...but for my frame I know I will be completely healthy and not underweight, just lean. It works both ways, so don't get too hung up on bmi!
  • willdob3
    willdob3 Posts: 640 Member
    BMI gives goals/results for things it cannot measure. I can't imagine ever taking it seriously.

    But, I also think it is ridiculous to base goals on scale weight, BF% or any other number. Numbers cannot guarantee one will be happy with how one looks or feels. Even those who say that they've weighed something before so that is what they want to weigh again can't be sure. Age & body composition change things.

Categories