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How do we judge a healthy weight range? BMI is no longer valid?
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3dogsrunning wrote: »
Because it takes about 2 seconds to do and, for the millionth time, is a good indicator for the majority. The links to support that are in CDC link I posted earlier. I'm on mobile and can't be bothered to get them
Know were I can get my BF analysis done? About 5 hours away. And for a hefty price.
Even when doing a health screening, how often would they be able to have the option of measuring BF?
Amazon can bring a unit to your door that will give you a better body fat analysis than BMI for under $40.
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MarkusDarwath wrote: »
I was picturing the wrong guy apparently, I don't follow sports. But in any case, he is very lean and NOT carrying that much in the way of extra muscle. If he were actually at 25% body fat he would definitely look borderline overweight. In other words, your own example has demonstrated BMI as a crappy estimator of body fat.
Oh. I guess my standards are different, but I think guys with 25% fat are overfat. Fiance is about 15% and still looks fat. Padded. He's well muscled and works out lifting 6 days a week, but does carry too much fat, according to the doctor - arms and legs big and pretty lean, butt is good, he's strong, it's belly all the way, that's where the last fat stays. He's overweight by BMI standards too. I think that for the vast majority of people, that window is good. It's a wide range to account for body types. He is, however, attractive to me and does not look fat compared to many Americans. I like the way he is built, but it's not the healthiest his body can be. So I do understand that many guys like to be bigger than what is the most healthy weight for them.
I do think BMI doesn't work right for estimating body fat, that part is true. But more likely to underestimate than overestimate.6 -
bennettinfinity wrote: »3dogsrunning wrote: »bennettinfinity wrote: »3dogsrunning wrote: »MarkusDarwath wrote: »middlehaitch wrote: »MarkusDarwath wrote: »One caveat about the thing with the belt, it can depend on how you wear your pants. The waist measurement for assessing body composition is supposed to be taken around the navel, whereas most men wear the 'waist' of their pants more toward the top of the hips. I wear size 36 pants, but my actual waist measurement is 47.5. Fortunately, my belly distension is not flabby, or I'd be sporting a major 'dunlap' aside from just being round.
So basically what you are saying is- you are obese with an unhealthy amount of visceral fat and you have problems with your BMI.
I'm saying I am obese and working on it, and BMI is completely irrelevant. Body Fat Percentage is a useful tool.
Irrelevant except for the large percentage of people it is a good indicator for.
How does one know if they're inside or outside the 'large percentage'? What is the 'large percentage'... the cumulative Normal at one standard deviation... two...? To me, this is what makes BMI a weak metric.
I don't disagree that it's a good indicator for those near mean height, but it doesn't scale well once you start moving away from the center of the distribution because the formula ignores the square-cube law.
(1) Are you in a category that you feel you do not fit? (2) If so, there are a number of other tools to use to evaluate if you are in the majority or one of the outliers.
Having body fat measured it one.
(1) I have no way of knowing - that's really the point.
(2) In a world where better (more meaningful, more accurate, more reliable) metrics are available, why do we need BMI? It reminds me of the Pop Tart commercials where the Pop Tarts are next to some eggs, toast, and orange juice: Part of this complete breakfast! The BMI is the Pop Tart of the health metric world.
My BMI is 26... am I overfat or overmuscular? Looking in the mirror will tell me more than "26" ever will.
At the end of the day, it's just a number, so I'm not too concerned about it per se. But when a metric doesn't apply equally to ALL, but it's used to measure ALL (and especially when it factors into how much one pays for health insurance, etc.), then I start to have a problem with it.
I don't disagree with your last point. But the thread was about judging a healthy weight. I still feel it's a decent place to start when trying to decide on a healthy weight.
you said you have no idea about number one but then say looking in the mirror tells you more. So you do know.0 -
According to his stats, Bolt is 6'5", 207 lbs. He is not even close to lean-looking IMHO. He is a solid chunk of impressive muscle. He is for sure an outlier, and his BMI is 24.5 which puts him on the high-side border of a healthy weight. Considering the caveat that BMI can be off for very muscular peeps, I think that validates BMI as a guideline.
And that's the key, BMI is not meant to be the "be all end all", though unfortunately some lazy insurance companies use it that way. It's one of many guidelines you can use, combined with how you feel and what your goals are, to determine if your weight is satisfactory or not. If we ever base whether or not you are put out on an iceberg or shipped to the soylent green facility by BMI, yeah I'll argue against it. But after reading this thread and considering everything I know, for the vast majority of people who just want an idea of what their goal weight should be, I think it's generally useful.7 -
MarkusDarwath wrote: »Lies and/or incompetence, take your pick. Govt in general can not be trusted with anything. Especially when talking about all these alphabet agencies who's existence is not even Constitutionally authorized.
Well, I can see that reason would be wasted here. Sure, it's The Vegans behind all of this.18 -
3dogsrunning wrote: »bennettinfinity wrote: »3dogsrunning wrote: »bennettinfinity wrote: »3dogsrunning wrote: »MarkusDarwath wrote: »middlehaitch wrote: »MarkusDarwath wrote: »One caveat about the thing with the belt, it can depend on how you wear your pants. The waist measurement for assessing body composition is supposed to be taken around the navel, whereas most men wear the 'waist' of their pants more toward the top of the hips. I wear size 36 pants, but my actual waist measurement is 47.5. Fortunately, my belly distension is not flabby, or I'd be sporting a major 'dunlap' aside from just being round.
So basically what you are saying is- you are obese with an unhealthy amount of visceral fat and you have problems with your BMI.
I'm saying I am obese and working on it, and BMI is completely irrelevant. Body Fat Percentage is a useful tool.
Irrelevant except for the large percentage of people it is a good indicator for.
How does one know if they're inside or outside the 'large percentage'? What is the 'large percentage'... the cumulative Normal at one standard deviation... two...? To me, this is what makes BMI a weak metric.
I don't disagree that it's a good indicator for those near mean height, but it doesn't scale well once you start moving away from the center of the distribution because the formula ignores the square-cube law.
(1) Are you in a category that you feel you do not fit? (2) If so, there are a number of other tools to use to evaluate if you are in the majority or one of the outliers.
Having body fat measured it one.
(1) I have no way of knowing - that's really the point.
(2) In a world where better (more meaningful, more accurate, more reliable) metrics are available, why do we need BMI? It reminds me of the Pop Tart commercials where the Pop Tarts are next to some eggs, toast, and orange juice: Part of this complete breakfast! The BMI is the Pop Tart of the health metric world.
My BMI is 26... am I overfat or overmuscular? Looking in the mirror will tell me more than "26" ever will.
At the end of the day, it's just a number, so I'm not too concerned about it per se. But when a metric doesn't apply equally to ALL, but it's used to measure ALL (and especially when it factors into how much one pays for health insurance, etc.), then I start to have a problem with it.
I don't disagree with your last point. But the thread was about judging a healthy weight. I still feel it's a decent place to start when trying to decide on a healthy weight.
you said you have no idea about number one but then say looking in the mirror tells you more. So you do know.
Yep.... I know... BMI is clueless.0 -
And I have always been told that bio-electrical impedance is at best only good to evaluate whether your BF% is trending up or down, not to get an accurate number.
I am about an hour outside of NYC, and I would have to go into the city to get DXA or hydrostatic weighing. Not practical.3 -
Yea, 25% is a lot of fat. What do they call that range? Acceptable I think is the term. Strikes me as the equivalent of a C student.MarkusDarwath wrote: »
I was picturing the wrong guy apparently, I don't follow sports. But in any case, he is very lean and NOT carrying that much in the way of extra muscle. If he were actually at 25% body fat he would definitely look borderline overweight. In other words, your own example has demonstrated BMI as a crappy estimator of body fat.
Oh. I guess my standards are different, but I think guys with 25% fat are overfat. Fiance is about 15% and still looks fat. Padded. He's well muscled and works out lifting 6 days a week, but does carry too much fat, according to the doctor - arms and legs big and pretty lean, butt is good, he's strong, it's belly all the way, that's where the last fat stays. He's overweight by BMI standards too. I think that for the vast majority of people, that window is good. It's a wide range to account for body types. He is, however, attractive to me and does not look fat compared to many Americans. I like the way he is built, but it's not the healthiest his body can be. So I do understand that many guys like to be bigger than what is the most healthy weight for them.
I do think BMI doesn't work right for estimating body fat, that part is true. But more likely to underestimate than overestimate.8 -
According to his stats, Bolt is 6'5", 207 lbs.
Right, he's a good normal size for his height, other than having much less fat than most.He is not even close to lean-looking IMHO. He is a solid chunk of impressive muscle.
Lean means "not fat". You can be lean at a low muscle mass or at a very high muscle mass.
The standard presented by the BMI charts promotes an "ideal" of normal to low body fat combined with low muscle mass. There is no health benefit to having less muscle. The average person would be healthier at a low-normal body fat with an amount of muscle that would push them to the top end of "healthy" or into "overweight" according to BMI. BMI is absolutely not an optimal health standard.
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bennettinfinity wrote: »In a world where better (more meaningful, more accurate, more reliable) metrics are available, why do we need BMI?
Since you can spend $1,000 on a bike wheel that measures your power output, why would anybody spend $50 on a heart rate monitor to guess at exertion levels?
Because BMI can be measured almost for free and an accurate measure of body fat involves considerably more expense. This matters for some applications.
Also, data quality matters. I have a bio-impedance scale, my %BF changes by a few points from one day to the next. So I have little confidence in my scale's ability to measure this. But my BMI is correct for me. I can tell by looking in the mirror that I'm not an outlier for BMI.
BMI is good for most of the population, and that allows population level reporting, for people to spot trends. We're not going to give everybody on the planet a monthly DEXA scan to have statistics like which states or countries have more/less obesity.
Have you ever heard the saying "don't let the perfect be the enemy of the good?"8 -
As stated numerous times already in this thread, BMI is accurate. I used to think I was some special snowflake, where it did not apply. And now I feel best when I'm at the lower end. So many people have no idea anymore what a healthy body weight looks like. That is why it's best to be whatever weight feels best for you.7
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And I have always been told that bio-electrical impedance is at best only good to evaluate whether your BF% is trending up or down, not to get an accurate number.
This is true, and yet it's still more accurate than BMI.
Or if you don't trust BIA there are a myriad of other formulas more accurate than BMI where you can take some measurements and type them into a web site. Height to waist ratio, and the formulas the military branches use when BMI fails and they "go to the tape" both come to mind.
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MarkusDarwath wrote: »And I have always been told that bio-electrical impedance is at best only good to evaluate whether your BF% is trending up or down, not to get an accurate number.
This is true, and yet it's still more accurate than BMI.
Or if you don't trust BIA there are a myriad of other formulas more accurate than BMI where you can take some measurements and type them into a web site. Height to waist ratio, and the formulas the military branches use when BMI fails and they "go to the tape" both come to mind.
You keep saying that. It isn't meant to be right for everyone nor does anyone claim that.
By going to a secondary measure they are using it exactly as it was meant to - as an indicator. And in that case it indicates someone *might* be overweight or in some cases of males, obese. Then they use other methods to determine if someone is, in fact, overweight. In some cases the follow up methods confirm the person is overweight. In others, that they are an outlier.6 -
NorthCascades wrote: »bennettinfinity wrote: »In a world where better (more meaningful, more accurate, more reliable) metrics are available, why do we need BMI?
Since you can spend $1,000 on a bike wheel that measures your power output, why would anybody spend $50 on a heart rate monitor to guess at exertion levels?
Because BMI can be measured almost for free and an accurate measure of body fat involves considerably more expense. This matters for some applications.
Also, data quality matters. I have a bio-impedance scale, my %BF changes by a few points from one day to the next. So I have little confidence in my scale's ability to measure this. But my BMI is correct for me. I can tell by looking in the mirror that I'm not an outlier for BMI.
BMI is good for most of the population, and that allows population level reporting, for people to spot trends. We're not going to give everybody on the planet a monthly DEXA scan to have statistics like which states or countries have more/less obesity.
Have you ever heard the saying "don't let the perfect be the enemy of the good?"
I don't recall mentioning bio-impedance or DEXA scans...
I'm 6'2", 203 lbs... BMI=26; "Overweight". Am I over by fat or am I over by muscle? BMI doesn't know and it doesn't care, but it makes a difference.
Am I healthy?
You don't know - and neither does BMI.1 -
NorthCascades wrote: »Because BMI can be measured almost for free and an accurate measure of body fat involves considerably more expense. This matters for some applications.
As I just pointed out, there are other almost free methods of assessing body fat that are more accurate than BMI.BMI is good for most of the population, ...........and that allows population level reporting,............ for people to spot trends.
I highlighted a very relevant point here. BMI was originally developed for populational studies, not for individual use. Using it to assess individual health is a misapplication of the formula.
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3dogsrunning wrote: »
You keep saying that. It isn't meant to be right for everyone nor does anyone claim that.
By going to a secondary measure they are using it exactly as it was meant to - as an indicator. And in that case it indicates someone *might* be overweight or in some cases of males, obese. Then they use other methods to determine if someone is, in fact, overweight. In some cases the follow up methods confirm the person is overweight. In others, that they are an outlier.
Then why bother with it when there are other methods that are just as cheap and easy?
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MarkusDarwath wrote: »And I have always been told that bio-electrical impedance is at best only good to evaluate whether your BF% is trending up or down, not to get an accurate number.
This is true, and yet it's still more accurate than BMI.
Or if you don't trust BIA there are a myriad of other formulas more accurate than BMI where you can take some measurements and type them into a web site. Height to waist ratio, and the formulas the military branches use when BMI fails and they "go to the tape" both come to mind.
You've said that unequivocally many times in this thread, but nothing you've said has IMO backed it up, so I have to respectfully disagree. I think the average person would need to get to a lower BF% than they will ever get to, and/or a higher lean muscle % than they will most likely get to, to end up in the "overweight" BMI category. And it is common knowledge in the communities where it matters (like athletes or the military for example) that in that outside chance that BMI says "overweight" but common sense says "not", you move on to other methods to clear up the discrepancy.6 -
MarkusDarwath wrote: »And I have always been told that bio-electrical impedance is at best only good to evaluate whether your BF% is trending up or down, not to get an accurate number.
This is true, and yet it's still more accurate than BMI.
Or if you don't trust BIA there are a myriad of other formulas more accurate than BMI where you can take some measurements and type them into a web site. Height to waist ratio, and the formulas the military branches use when BMI fails and they "go to the tape" both come to mind.
I find it interesting that you bring up the height to waist ratio. I am about 5'3.5" so my healthy waist measurement is under 32". However, at 140 pounds (24.4 BMI) my waist was just over that measurement indicating that I was overfat even though BMI had me at the high end of "normal weight." I don't know if I was actually at an unhealthy weight or not. My torso is very short, so my waist will never be tiny.
TL;DR The height to waist ratio measurement is even less forgiving than BMI for some of us.7 -
MarkusDarwath wrote: »Packerjohn wrote: »MarkusDarwath wrote: »One caveat about the thing with the belt, it can depend on how you wear your pants. The waist measurement for assessing body composition is supposed to be taken around the navel, whereas most men wear the 'waist' of their pants more toward the top of the hips. I wear size 36 pants, but my actual waist measurement is 47.5. Fortunately, my belly distension is not flabby, or I'd be sporting a major 'dunlap' aside from just being round.
Sorry, as has been mentioned before you are wearing size 36 pants because you have a large amount of visceral fat. The location of the fat forces your pants to fit that way. Most men don't wear a pants size 12 inches less than their waist size.
I never claimed I didn't. I was merely pointing out that using your belt size as an indicator is not going to be accurate if your belly is larger than your belt. If I assessed myself based on my pants size, it would suggest I'm in pretty decent shape, which clearly is not the case.
None of the measurements that use a ratio use belt size as a factor. They use waist measuremnt at the natural waist (you can Google and find where that is) vs height ot hips measurement.3 -
just my 2 cents worth here, I believe that while BMI can be a useful tool in determining a healthy weight, it is not the only tool that can be used. Personally, I track a variety of things to tell me how I'm doing, including my BMI, my waist to hip ratio, my waist to height ratio, and a rough estimate of my BF% (figured out from an average of 3 different online calculators and a set of calipers that I own) to figure out my healthy weight range. BMI in my opinion is a good starting point for those who aren't as familiar with different ways of measuring their progress.2
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