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BMI calculations...
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Of course you do.3
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BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS.
That's not my understanding of what BMI is for at all.
It's a screening tool. Statistically, people beyond the normal BMI range have an increased risk of negative health effects. It's a simple and quick quide to help decide if further information is needed (all you need is height and weight - of course it's simplistic, but it's easy to use and overall a helpful indicator).
Of course it's prefectly possible to be healthy beyond the standard BMI range (and sometimes be unhealthy within it), bit it's not meant as an estimate of health by itself.
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It's a good guideline for many and inaccurate for a few - that's how population measures work.
But far too many think they are one of the few!
^^^^ This.
Here's an illustration: The average number of children born per woman in the US in 2016 is 1.87. Yet I know of no one who actually has 1.87 children.
Source: CIA World Factbook
(https://www.cia.gov/library/publications/the-world-factbook/fields/2127.html)6 -
stevencloser wrote: »BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS. There are lots of unhealthy people at a "healthy BMI" and you don't have to look anything like the Rock to be at an overweight or even obese BMI, particularly men. If you want to know if you are healthy, look in the mirror, actually check your body fat, check your blood pressure, check your cholesterol, etc.
Yeah, it's so easy to be obese by BMI without being overfat, a 6 foot person would just have to be 220 pounds, putting them at least at 24 FFMI, and that's when you're at 20% bodyfat which is hardly the best bodyfat amount to have. That goes up to 26 if you go with an actually healthy bodyfat range. 25 FFMI is what's regarded barely still doable by people with great genetics. But yeah tell yourself so many people at healthy bodyfat amounts can be up to obese without that crazy amount of muscle.
I swear, the skewed perception perpetuated thanks to pro bodybuilders is gonna be the death of my sanity.
First of all, you skipped the overweight range entirely. Secondly, use whatever calculations you want but it really isn't that hard to exceed the normal or even overweight BMI ranges and be healthy. Last time I lost weight, I was still considered obese according to BMI charts but had abs showing and a 32" waist. That was after only 3 months back in the gym. A couple of guys I work with have 6 packs and are both overweight according to BMI and one of them can't even bench 300. I would hardly call that a bodybuilder.
I have abs, a 30" and a BMI slightly in the overweight range and I bench 1.6x my bodyweight, but so what? What does that have to do with most people? Those of us who know the BMI doesn't work for us aren't that fussed about it in general because we know it's a population measure. For individuals it's just one of many tools and there are better ones for individuals, but a BMI measurement can still be a good check.
Also, I seriously doubt you were in the obese range with a 10-15% BF unless you were running a decent stack. As Steve pointed out, you need to have a FFM that's extremely high and isn't something you get without drugs and years of serious training. Out of all of the bodybuilders, powerlifters, weight lifters (i.e. Olympic lifting) or wresters I've ever known (and I known tons), only a handful would ever have been BMI rated obese AND have an athletic BF% and they all had pro cards. I'm also not even going to touch the fact that these bodybuilders aren't really that healthy and their life expectancy is still reduced. It doesn't really matter how you get to obese BMI it doesn't seem to do much for longevity either way.10 -
BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS.
That's not my understanding of what BMI is for at all.
It's a screening tool. Statistically, people beyond the normal BMI range have an increased risk of negative health effects. It's a simple and quick quide to help decide if further information is needed (all you need is height and weight - of course it's simplistic, but it's easy to use and overall a helpful indicator).
Of course it's prefectly possible to be healthy beyond the standard BMI range (and sometimes be unhealthy within it), bit it's not meant as an estimate of health by itself.
There is even some evidence that being slightly above 25 but active and not on a yo-yo diet cycle can be better than being in normal range but having to fight to stay there all the time.
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TrevorMcC85 wrote: »Hi everyone,
This has probably already been discussed but I would like to ask those in the know if BMI calculations are accurate?
I have read a few articles recently that speak negatively about them, even going as far to say that they are completely pointless.
I'm just starting out trying to get fit and healthy and am wondering is it a good measurement of where I am and where I would like to be?
Any help would be appreciated!
Trevor
BMI will be a rough guide only but should help you know where you should approximately be. Better measures for you would be BF% plus hip to waist ratio. It's not just how much fat you have but where you store it that's important and visceral fat should be minimized.0 -
They are a pretty good guideline in general.
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Wheelhouse15 wrote: »stevencloser wrote: »BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS. There are lots of unhealthy people at a "healthy BMI" and you don't have to look anything like the Rock to be at an overweight or even obese BMI, particularly men. If you want to know if you are healthy, look in the mirror, actually check your body fat, check your blood pressure, check your cholesterol, etc.
Yeah, it's so easy to be obese by BMI without being overfat, a 6 foot person would just have to be 220 pounds, putting them at least at 24 FFMI, and that's when you're at 20% bodyfat which is hardly the best bodyfat amount to have. That goes up to 26 if you go with an actually healthy bodyfat range. 25 FFMI is what's regarded barely still doable by people with great genetics. But yeah tell yourself so many people at healthy bodyfat amounts can be up to obese without that crazy amount of muscle.
I swear, the skewed perception perpetuated thanks to pro bodybuilders is gonna be the death of my sanity.
First of all, you skipped the overweight range entirely. Secondly, use whatever calculations you want but it really isn't that hard to exceed the normal or even overweight BMI ranges and be healthy. Last time I lost weight, I was still considered obese according to BMI charts but had abs showing and a 32" waist. That was after only 3 months back in the gym. A couple of guys I work with have 6 packs and are both overweight according to BMI and one of them can't even bench 300. I would hardly call that a bodybuilder.
I have abs, a 30" and a BMI slightly in the overweight range and I bench 1.6x my bodyweight, but so what? What does that have to do with most people? Those of us who know the BMI doesn't work for us aren't that fussed about it in general because we know it's a population measure. For individuals it's just one of many tools and there are better ones for individuals, but a BMI measurement can still be a good check.
Also, I seriously doubt you were in the obese range with a 10-15% BF unless you were running a decent stack. As Steve pointed out, you need to have a FFM that's extremely high and isn't something you get without drugs and years of serious training. Out of all of the bodybuilders, powerlifters, weight lifters (i.e. Olympic lifting) or wresters I've ever known (and I known tons), only a handful would ever have been BMI rated obese AND have an athletic BF% and they all had pro cards. I'm also not even going to touch the fact that these bodybuilders aren't really that healthy and their life expectancy is still reduced. It doesn't really matter how you get to obese BMI it doesn't seem to do much for longevity either way.
The only way I can see someone who does not have unreasonably high lean mass having abs and being in the obese range, is someone with extreme levels of visceral fat and little subcutaneous, which needless to say is very unhealthy.2 -
stevencloser wrote: »Wheelhouse15 wrote: »stevencloser wrote: »BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS. There are lots of unhealthy people at a "healthy BMI" and you don't have to look anything like the Rock to be at an overweight or even obese BMI, particularly men. If you want to know if you are healthy, look in the mirror, actually check your body fat, check your blood pressure, check your cholesterol, etc.
Yeah, it's so easy to be obese by BMI without being overfat, a 6 foot person would just have to be 220 pounds, putting them at least at 24 FFMI, and that's when you're at 20% bodyfat which is hardly the best bodyfat amount to have. That goes up to 26 if you go with an actually healthy bodyfat range. 25 FFMI is what's regarded barely still doable by people with great genetics. But yeah tell yourself so many people at healthy bodyfat amounts can be up to obese without that crazy amount of muscle.
I swear, the skewed perception perpetuated thanks to pro bodybuilders is gonna be the death of my sanity.
First of all, you skipped the overweight range entirely. Secondly, use whatever calculations you want but it really isn't that hard to exceed the normal or even overweight BMI ranges and be healthy. Last time I lost weight, I was still considered obese according to BMI charts but had abs showing and a 32" waist. That was after only 3 months back in the gym. A couple of guys I work with have 6 packs and are both overweight according to BMI and one of them can't even bench 300. I would hardly call that a bodybuilder.
I have abs, a 30" and a BMI slightly in the overweight range and I bench 1.6x my bodyweight, but so what? What does that have to do with most people? Those of us who know the BMI doesn't work for us aren't that fussed about it in general because we know it's a population measure. For individuals it's just one of many tools and there are better ones for individuals, but a BMI measurement can still be a good check.
Also, I seriously doubt you were in the obese range with a 10-15% BF unless you were running a decent stack. As Steve pointed out, you need to have a FFM that's extremely high and isn't something you get without drugs and years of serious training. Out of all of the bodybuilders, powerlifters, weight lifters (i.e. Olympic lifting) or wresters I've ever known (and I known tons), only a handful would ever have been BMI rated obese AND have an athletic BF% and they all had pro cards. I'm also not even going to touch the fact that these bodybuilders aren't really that healthy and their life expectancy is still reduced. It doesn't really matter how you get to obese BMI it doesn't seem to do much for longevity either way.
The only way I can see someone who does not have unreasonably high lean mass having abs and being in the obese range, is someone with extreme levels of visceral fat and little subcutaneous, which needless to say is very unhealthy.
It's an unnatural fat distribution and the only people you see with protruding bellies and abs are the mass monsters in the IFBB who take large amounts of IGF-1 and thus have swollen internal organs. It's still not healthy to be like that and looks ridiculous.1 -
All I will say is that a few years ago, my doctor was all about BMI. Now he tends to be more concerned with waist to hip ratios along with BMI. For example, my husband is a fairly fit and strong guy who is at a good weight and works out regularly, but he still has metabolic syndrome. He could probably lose another 5-10 pounds, but he is within a fairly "healthy" BMI for his height. Our doctor is most concerned about his WHR. Whereas, my doctor would be thrilled if I just lowered my BMI by 7-10 points, even though I would still be in the "obese" range.
I think BMI is a good "guideline" but there are other indicators of health (like WHR, bloodwork, genetics, etc.) that should be taken into consideration.0 -
All I will say is that a few years ago, my doctor was all about BMI. Now he tends to be more concerned with waist to hip ratios along with BMI. For example, my husband is a fairly fit and strong guy who is at a good weight and works out regularly, but he still has metabolic syndrome. He could probably lose another 5-10 pounds, but he is within a fairly "healthy" BMI for his height. Our doctor is most concerned about his WHR. Whereas, my doctor would be thrilled if I just lowered my BMI by 7-10 points, even though I would still be in the "obese" range.
I think BMI is a good "guideline" but there are other indicators of health (like WHR, bloodwork, genetics, etc.) that should be taken into consideration.
I'm a bit surprised someone with a "healthy" BMI has a WHR a doctor would be considered about. Especially when you say he works out regularly.0 -
Packerjohn wrote: »All I will say is that a few years ago, my doctor was all about BMI. Now he tends to be more concerned with waist to hip ratios along with BMI. For example, my husband is a fairly fit and strong guy who is at a good weight and works out regularly, but he still has metabolic syndrome. He could probably lose another 5-10 pounds, but he is within a fairly "healthy" BMI for his height. Our doctor is most concerned about his WHR. Whereas, my doctor would be thrilled if I just lowered my BMI by 7-10 points, even though I would still be in the "obese" range.
I think BMI is a good "guideline" but there are other indicators of health (like WHR, bloodwork, genetics, etc.) that should be taken into consideration.
I'm a bit surprised someone with a "healthy" BMI has a WHR a doctor would be considered about. Especially when you say he works out regularly.
You can have a normal BMI and have a ratio that is high, this would be a person who is apple shaped and likely pre-diabetic.1 -
mumblemagic wrote: »This article explains the stats on bmi accuracy as regards a measurement of over-fatness.
TL;DR BMI is not the best measure of over-fatness and the cut-offs as they are have a tendancy to *under*-detect over-fatness. However, there are health risks of having a high bmi even if you have a low body fat. So, if you have a high bmi losing weight could be good for you regardless of fatness, and you shouldn't lull yourself into a false sense of security if you have a low bmi because you could still be over-fat.
http://evidencebasedfitness.net/lack-of-basic-epidemiology-knowledge-makes-us-all-dumber/
Yes, exactly. BMI is inaccurate, but not in the direction people assume. You are more likely to be overfat without being overweight, than to be overweight without being overfat.
Put much more succinctly than me :-)
Another thing to add: waist to height ratio is a better indicator of health outcomes for some but not all "weight" related conditions because it is a better proxy measure of fat around the organs - visceral fat, but not all fat or weight related illnesses are just about visceral fat.
Ultimately, if you aim for your bmi, bf%, and wth ratio to be in the middle of the recommended ranges, you'll minimise your risk of all weight, fat, and visceral fat related illnesses. What the hard cut-offs are is somewhat irrelevant if you are going for optimum loss/toning rather than minimum.1 -
I hate the WHR method. I have narrow hips, so no matter how slim I get, I am always considered "at risk."
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Mouse_Potato wrote: »I hate the WHR method. I have narrow hips, so no matter how slim I get, I am always considered "at risk."
All tools have their limits when it comes to individual results. Waist to height might be more accurate for you.0 -
Back in high school, a friend of mine pointed out to me that the kids in my school who opposed P.E (gym class) the most were overweight.
Imo, the same applies here. Those who denounce the BMI chart the loudest tend to be overweight. Also good to notice that very often, BMI is oh-so-accurate if someone mentions that they're even one pound underweight, but if someone is one pound or more overweight, it's okay because screw BMI calculations.
Bottom line, BMI, as many have already written here, is generally accurate enough for the masses.6 -
I think BF% is a better metric than BMI. I'd say it's more common to find overfat people at "healthy" BMIs than it is to find people with high BMI and low BF%. With that said, while BMI was originally intended to be a statistic used to study populations, not individuals, it's at least a valid ballpark figure for the vast majority of people.
Some people seem to like to throw groups such as pro football players out there as examples of why BMI isn't valid. There are a couple factors complicating that argument: 1) Many pro football players are using PEDs, which will make them outliers in terms of muscle mass. 2) If you look at linemen (who are the "behemoths" of the NFL), they're carrying quite a bit of bodyfat along with their muscle. It's rare to see an offensive lineman who isn't at least 30-35% BF. No denying they're strong as bears and in better physical shape than the general population, but that still doesn't change the fact that carrying all that extra fat has the potential to create health issues.8 -
Wheelhouse15 wrote: »stevencloser wrote: »BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS. There are lots of unhealthy people at a "healthy BMI" and you don't have to look anything like the Rock to be at an overweight or even obese BMI, particularly men. If you want to know if you are healthy, look in the mirror, actually check your body fat, check your blood pressure, check your cholesterol, etc.
Yeah, it's so easy to be obese by BMI without being overfat, a 6 foot person would just have to be 220 pounds, putting them at least at 24 FFMI, and that's when you're at 20% bodyfat which is hardly the best bodyfat amount to have. That goes up to 26 if you go with an actually healthy bodyfat range. 25 FFMI is what's regarded barely still doable by people with great genetics. But yeah tell yourself so many people at healthy bodyfat amounts can be up to obese without that crazy amount of muscle.
I swear, the skewed perception perpetuated thanks to pro bodybuilders is gonna be the death of my sanity.
First of all, you skipped the overweight range entirely. Secondly, use whatever calculations you want but it really isn't that hard to exceed the normal or even overweight BMI ranges and be healthy. Last time I lost weight, I was still considered obese according to BMI charts but had abs showing and a 32" waist. That was after only 3 months back in the gym. A couple of guys I work with have 6 packs and are both overweight according to BMI and one of them can't even bench 300. I would hardly call that a bodybuilder.
I have abs, a 30" and a BMI slightly in the overweight range and I bench 1.6x my bodyweight, but so what? What does that have to do with most people? Those of us who know the BMI doesn't work for us aren't that fussed about it in general because we know it's a population measure. For individuals it's just one of many tools and there are better ones for individuals, but a BMI measurement can still be a good check.
Also, I seriously doubt you were in the obese range with a 10-15% BF unless you were running a decent stack. As Steve pointed out, you need to have a FFM that's extremely high and isn't something you get without drugs and years of serious training. Out of all of the bodybuilders, powerlifters, weight lifters (i.e. Olympic lifting) or wresters I've ever known (and I known tons), only a handful would ever have been BMI rated obese AND have an athletic BF% and they all had pro cards. I'm also not even going to touch the fact that these bodybuilders aren't really that healthy and their life expectancy is still reduced. It doesn't really matter how you get to obese BMI it doesn't seem to do much for longevity either way.
The debate isn't whether BMI is a reasonable range for most people. The argument people are making is that it accurate for all but super rare cases. What I am saying is that there is a significant amount of people for whom BMI isn't accurate and I am also saying it tells very little of a person's overall health. As for me, I was benching 1.75 times my body weight and I really don't know what my body fat % was but I certainly wasn't "overfat". Also, I have never touched steroids of any kind, ever. BMI is nothing more than laziness. It exists only because it is easy. If you want to know if you are fat, check your bf% or look in the mirror. If you want to know if you are healthy, check your heart rate and blood pressure and have blood work done.0 -
For my 7 year old it is completely pointless. She is a gymnast and trains 8 hours a week, full on training. She has a lot of muscle, she has no fat on her at all, a six pack yet her BMI is close to being overweight?0
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Wheelhouse15 wrote: »stevencloser wrote: »BMI is all but worthless. It is supposed to be a reasonable estimate of a healthy level of body fat and in that regard it BS. There are lots of unhealthy people at a "healthy BMI" and you don't have to look anything like the Rock to be at an overweight or even obese BMI, particularly men. If you want to know if you are healthy, look in the mirror, actually check your body fat, check your blood pressure, check your cholesterol, etc.
Yeah, it's so easy to be obese by BMI without being overfat, a 6 foot person would just have to be 220 pounds, putting them at least at 24 FFMI, and that's when you're at 20% bodyfat which is hardly the best bodyfat amount to have. That goes up to 26 if you go with an actually healthy bodyfat range. 25 FFMI is what's regarded barely still doable by people with great genetics. But yeah tell yourself so many people at healthy bodyfat amounts can be up to obese without that crazy amount of muscle.
I swear, the skewed perception perpetuated thanks to pro bodybuilders is gonna be the death of my sanity.
First of all, you skipped the overweight range entirely. Secondly, use whatever calculations you want but it really isn't that hard to exceed the normal or even overweight BMI ranges and be healthy. Last time I lost weight, I was still considered obese according to BMI charts but had abs showing and a 32" waist. That was after only 3 months back in the gym. A couple of guys I work with have 6 packs and are both overweight according to BMI and one of them can't even bench 300. I would hardly call that a bodybuilder.
I have abs, a 30" and a BMI slightly in the overweight range and I bench 1.6x my bodyweight, but so what? What does that have to do with most people? Those of us who know the BMI doesn't work for us aren't that fussed about it in general because we know it's a population measure. For individuals it's just one of many tools and there are better ones for individuals, but a BMI measurement can still be a good check.
Also, I seriously doubt you were in the obese range with a 10-15% BF unless you were running a decent stack. As Steve pointed out, you need to have a FFM that's extremely high and isn't something you get without drugs and years of serious training. Out of all of the bodybuilders, powerlifters, weight lifters (i.e. Olympic lifting) or wresters I've ever known (and I known tons), only a handful would ever have been BMI rated obese AND have an athletic BF% and they all had pro cards. I'm also not even going to touch the fact that these bodybuilders aren't really that healthy and their life expectancy is still reduced. It doesn't really matter how you get to obese BMI it doesn't seem to do much for longevity either way.
The debate isn't whether BMI is a reasonable range for most people. The argument people are making is that it accurate for all but super rare cases. What I am saying is that there is a significant amount of people for whom BMI isn't accurate and I am also saying it tells very little of a person's overall health. As for me, I was benching 1.75 times my body weight and I really don't know what my body fat % was but I certainly wasn't "overfat". Also, I have never touched steroids of any kind, ever. BMI is nothing more than laziness. It exists only because it is easy. If you want to know if you are fat, check your bf% or look in the mirror. If you want to know if you are healthy, check your heart rate and blood pressure and have blood work done.
The last part I agree with, even if you are in range you should have your blood screens and BP taken. Oh, and 1.75 is certainly within the range of naturals, my best when I was younger was 1.9xBW and that's not even in the elite range, what I was referring to was being obese BMI and having visible abs. You can be 25% and not overfat but obese BMI. BMI can be slightly off on the edges but those are always grey anyway. Of course, me defendig BMI is kinda odd lol, I don't really like it as an individual measure but rather a population metric.1
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