Is BMI an accurate way to know how much I should weigh?
Options
Replies
-
BMI is meant to be a general guide, when taken into consideration with other metrics like waist measurement, body fat %, and blood work and other medical metrics. It is a good general guide for the vast majority of people. But it is no guarantee of predicting a healthy weight for every individual, it's not intended to be. The fact that there are outliers doesn't make it useless.
If you've had a physical and gotten a clean bill of health recently, and your waist measurement is within the healthy range, then being slightly over the healthy BMI might not mean anything.
It is doubtful anyone would be an outlier without realizing it. If you are very tall, very short, or heavily muscled you may be at a healthy weight while outside the BMI range. If you're concerned, get a physical and blood work and discuss it with your doctor.
Unfortunately it is not uncommon for people to convince themselves they are "muscular" because they go to the gym sometimes, or have a naturally large frame and muscular build, when they really are just overweight. If you are outside the healthy weight range and think it's because you are muscular but have no idea what your bf % is, consult a pro to confirm that. Or if you're happy where you are, and your doctor is unconcerned, just don't worry about it. BMI isn't intended to be the be all and end all, just one of several data points.
"Health" is not a yes or no question, it's a sliding scale. How much of a health risk extra weight conveys is still an open scientific question - all we have is correlation. What is healthy enough for your priorities and comfort level is a personal decision. There's no harm in eating at a deficit for a couple of months, losing a few lbs, and seeing how you feel and look and going from there. If you lose weight slowly, you shouldn't lose appreciable muscle. Regardless, it's certainly nothing to panic about9 -
I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?2
-
Im afraid I still dont know what your argument is - nobody, certainly not me, was arguing that ethnic groups cannot have slightly different ranges of healthy BMI
You dont have to have read my posts in other threads - I said in this thread some people are slightly out of the range and still healthy.
My further post just gave an example, which I have used before.
Very few people, unless obvious outliers, will be a healthy weight very far out of standard BMI range.
Not just sedentary people - all people.6 -
What is very far out of standard BMI range? If we're talking about a bmi of 27 versus a bmi of 25, that's a difference of 15lbs. It is quite significant don't you think?
2 -
No I don't.
4 -
Is a bmi of 29 very far out of the healthy range? We're talking about a difference of 25lbs, about what a man can gain in muscle mass with a year of training.0
-
paperpudding wrote: »nonachalke wrote: »I looked up my BMI last night and it says I’m overweight, so obviously I’m freaking out. But is it accurate? I don’t want to just lose weight, I want to get toned and strong, I like muscle on me, but how do I know how much I should weigh?!
For almost everybody, yes it is accurate -
Unless you have have a really high muscle percentage, meaning elite body builder high, or you are some other sort of outlier
I will have to quote you, because even an experienced lifter who's healthy at a bmi of 30 is not elite bodybuilder status. I guess i'm a little bit confused by your choice of words.
0 -
I think what I said is quite clear, sorry if you find it confusing.
Not getting caught up in semantics of word choices. You can play that game by yourself.5 -
nonachalke wrote: »I looked up my BMI last night and it says I’m overweight, so obviously I’m freaking out. But is it accurate? I don’t want to just lose weight, I want to get toned and strong, I like muscle on me, but how do I know how much I should weigh?!
I think BMI is a pretty good target to aim at. Is it the be all and all? No.7 -
I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?
A recent study reported that 8.9 percent of Americans had done some kind of weight lifting in a typical day (this seems high to be, but what do I know?). The number of people who are doing it at a level to drive their BMI into the overweight range even though their body fat is at a healthy level is not recorded, but it's going to be much, much less than that. In contrast, 2/3s of Americans are in the overweight or obese range. We're not dealing with a nation of Dwayne Johnsons being falsely diagnosed with obesity. We're talking about a whole bunch of overweight people. I don't have the stats for Canada, but I am not aware of any evidence showing it's an issue there either.9 -
janejellyroll wrote: »I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?
A recent study reported that 8.9 percent of Americans had done some kind of weight lifting in a typical day (this seems high to be, but what do I know?). The number of people who are doing it at a level to drive their BMI into the overweight range even though their body fat is at a healthy level is not recorded, but it's going to be much, much less than that. In contrast, 2/3s of Americans are in the overweight or obese range. We're not dealing with a nation of Dwayne Johnsons being falsely diagnosed with obesity. We're talking about a whole bunch of overweight people. I don't have the stats for Canada, but I am not aware of any evidence showing it's an issue there either.
I think there's an assumption built into that idea (of lots of people being overweight per BMI but muscular, so at a good weight) that many people belong toward the upper end of the normal range to start with, before adding unusual amounts of muscle. I'm unconvinced, especially if we're talking about women.
*Some* people are at a near-ideal weight per body fat %, but at overweight BMI? Sure. *Lots* of people? I don't think so.
I'd have to add around 20 pounds of muscle to accomplish that, and I'm not at zero muscle now, or terribly delicate of build skeletally. It's not gonna happen, even if I were working hard for it.
My scepticism is probably amplified by people I've seen make the claim in real life, I admit.
People can choose to be the weight they prefer. Stats suggest being a bit into the overweight BMI zone is not a terrible health risk, besides.
To the bolded: Probably self-reported. 😉😆4 -
janejellyroll wrote: »I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?
A recent study reported that 8.9 percent of Americans had done some kind of weight lifting in a typical day (this seems high to be, but what do I know?). The number of people who are doing it at a level to drive their BMI into the overweight range even though their body fat is at a healthy level is not recorded, but it's going to be much, much less than that. In contrast, 2/3s of Americans are in the overweight or obese range. We're not dealing with a nation of Dwayne Johnsons being falsely diagnosed with obesity. We're talking about a whole bunch of overweight people. I don't have the stats for Canada, but I am not aware of any evidence showing it's an issue there either.
I think there's an assumption built into that idea (of lots of people being overweight per BMI but muscular, so at a good weight) that many people belong toward the upper end of the normal range to start with, before adding unusual amounts of muscle. I'm unconvinced, especially if we're talking about women.
*Some* people are at a near-ideal weight per body fat %, but at overweight BMI? Sure. *Lots* of people? I don't think so.
I'd have to add around 20 pounds of muscle to accomplish that, and I'm not at zero muscle now, or terribly delicate of build skeletally. It's not gonna happen, even if I were working hard for it.
My scepticism is probably amplified by people I've seen make the claim in real life, I admit.
People can choose to be the weight they prefer. Stats suggest being a bit into the overweight BMI zone is not a terrible health risk, besides.
To the bolded: Probably self-reported. 😉😆
Yeah, I'm skeptical that many people are regularly weight lifting, let alone regularly weight lifting to the point where they need to be concerned about adding 20+ pounds of muscle to their body.9 -
janejellyroll wrote: »We're not dealing with a nation of Dwayne Johnsons being falsely diagnosed with obesity.
^^^This...
9 -
janejellyroll wrote: »I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?
A recent study reported that 8.9 percent of Americans had done some kind of weight lifting in a typical day (this seems high to be, but what do I know?). The number of people who are doing it at a level to drive their BMI into the overweight range even though their body fat is at a healthy level is not recorded, but it's going to be much, much less than that. In contrast, 2/3s of Americans are in the overweight or obese range. We're not dealing with a nation of Dwayne Johnsons being falsely diagnosed with obesity. We're talking about a whole bunch of overweight people. I don't have the stats for Canada, but I am not aware of any evidence showing it's an issue there either.
To the bolded: Probably self-reported. 😉😆
And that includes reporting the 1 lb pink dumbbell tri-kickbacks done after the cardio workout.
Did they report wearing purple ankle warmers?6 -
janejellyroll wrote: »I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?
A recent study reported that 8.9 percent of Americans had done some kind of weight lifting in a typical day (this seems high to be, but what do I know?). The number of people who are doing it at a level to drive their BMI into the overweight range even though their body fat is at a healthy level is not recorded, but it's going to be much, much less than that. In contrast, 2/3s of Americans are in the overweight or obese range. We're not dealing with a nation of Dwayne Johnsons being falsely diagnosed with obesity. We're talking about a whole bunch of overweight people. I don't have the stats for Canada, but I am not aware of any evidence showing it's an issue there either.
To the bolded: Probably self-reported. 😉😆
And that includes reporting the 1 lb pink dumbbell tri-kickbacks done after the cardio workout.
Did they report wearing purple ankle warmers?
So much this!
Of that small percentage saying they train few are actually training effectively to build significant amounts of muscle even if that's actually their goal. A lot of them are cross-training, maintaining what they have, vaguely trying to get in shape or just messing about with very light weights and ineffective / inconsistent training regimes.
As the OP (before she freaked out never to be seen again...) said "I want to get toned and strong" rather than she is strong and unusually well muscled the chances are that BMI has given her a reasonable nudge in the right direction. Denial isn't just a big river that runs through Egypt....
For the very few overweight by BMI due to unusually high muscle mass individuals at my gym no medic in their right mind using BMI as a screening / risk assessment tool would be concerned.
6 -
I agree with all of that, it is not useless, it's probably useful for 90% of the population. And there are a lot of questions, for exemple, what is the percentage of the population who lift weights or do resistance training on a regular basis?
I've lifted for years...my wife has lifted for years. Most people I know hitting the weight room are trying to stay in shape and stay healthy and fit...I know very few people engaging in bodybuilding and packing on 20 Lbs of muscle in a year...which by the way would also add a fair bit of fat. Most people I know who are fairly muscular and overweight per BMI, also carry excess fat...they look better than couch potato fat...but they still are carrying some excess fat...they aren't super lean. The only guy I know who is 6 pack lean and overweight per BMI is my trainer and he is a retired professional athlete.
I'm definitely not huge, but have a fair bit of muscle mass...my maintenance weight is right around 180 which puts me at the very high end of the BMI scale for my height....and I'm not super lean at that weight either, no visible abs or anything like that...around 15% BF. I'm currently sitting at around 193 Lbs which is 10 Lbs overweight per BMI...I carry it pretty well and in general I'm in pretty good shape, so it visibly looks better than a 193 Lb couch potato...but it's not like it's an extra 10 Lbs of muscle from doing some deadlifts and bench press...it's 10 Lbs of pandemic Doritos and beer.11 -
what if you have large dense bones and dense tissue? i continually have issues with MRI's, etc. because my tissue is "dense" (their word, not mine) and my wrist bone is over 8" in size. I'm built like my short stocky Italian grandfather. I don't believe the typical BMI chart would be accurate. How else do we measure bodyfat?2
-
azalea4175 wrote: »what if you have large dense bones and dense tissue? i continually have issues with MRI's, etc. because my tissue is "dense" (their word, not mine) and my wrist bone is over 8" in size. I'm built like my short stocky Italian grandfather. I don't believe the typical BMI chart would be accurate. How else do we measure bodyfat?
BMI is not assessing body fat at all. You'd still want to use the traditional tools (calipers, scanners, etc) to understand your body fat.4 -
azalea4175 wrote: »what if you have large dense bones and dense tissue? i continually have issues with MRI's, etc. because my tissue is "dense" (their word, not mine) and my wrist bone is over 8" in size. I'm built like my short stocky Italian grandfather. I don't believe the typical BMI chart would be accurate. How else do we measure bodyfat?
Yeah, BMI doesn't measure bodyfat...BMI is a population statistical tool to *kitten* potential health risks from being over or under weight. It is a pretty broad range of weight to account for things such as frame, muscle mass, etc. For most people, somewhere on the BMI range for their height is going to result in a healthy weight.
My wife is built stocky and has more muscle mass than average for a woman...she was a college rugby and soccer player and has been lifting and training since her late teens. The high end of BMI for her height is 126 Lbs...she typically maintains at the higher end...usually between 120 and 125 despite having a larger frame and bone structure and a solid amount of muscle mass...she's around 135 right now and both of us have about 10 Lbs of COVID fluff we need to lose.
Once upon a time, neither one of us believed that BMI was really appropriate for us, or that it was just impossible...come to find out it is, albeit we both maintain on the higher end of our respective ranges.8 -
Is a bmi of 29 very far out of the healthy range? We're talking about a difference of 25lbs, about what a man can gain in muscle mass with a year of training.
Lifting weights a few times a week does not mean that you will me adding muscle mass.
For a man to gain 20 to 25 lbs of muscle in a year, they would have to be dedicated to the gym (2-3 hours of lifting a day, 6 days a week, with a very regimented lifting schedule) and be very dedicated to nutrition/calories/sleep schedules/etc. That kind of growth (outside of some test fueled teens) takes a monumental amount of effort and does not just 'happen' for the guys who show up 3-4 times a week and do some curls/bench/deads/squats.
The average Joe that goes to the gym 2-3 times a week and does some curls/bench/deads/squats will NOT be putting on an appreciable amount of muscle over a year or even a more extended timeframe.
Oh, and don't confuse getting stronger (i.e. lifting more) with adding muscle. A lot of the gains that lifters see are not from adding muscle mass - it comes from training the muscles and nervous system to react to the loads that you are moving. I personally have tripled my bench/curl/tricep extention maxes and working loads in a year and only added 1/4 of an inch to my arms and chest.
TL//DR - it takes a lot of work and dedication to add muscle mass and casual lifters don't add an appreciable amount of mass over extended time frames. So the strawman arguments about the mythical guy who adds 20 lbs of muscle in a year are moot.10
Categories
- All Categories
- 1.4M Health, Wellness and Goals
- 391.5K Introduce Yourself
- 43.5K Getting Started
- 259.7K Health and Weight Loss
- 175.6K Food and Nutrition
- 47.3K Recipes
- 232.3K Fitness and Exercise
- 392 Sleep, Mindfulness and Overall Wellness
- 6.4K Goal: Maintaining Weight
- 8.5K Goal: Gaining Weight and Body Building
- 152.7K Motivation and Support
- 7.8K Challenges
- 1.3K Debate Club
- 96.3K Chit-Chat
- 2.5K Fun and Games
- 3.2K MyFitnessPal Information
- 22 News and Announcements
- 926 Feature Suggestions and Ideas
- 2.3K MyFitnessPal Tech Support Questions