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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.
If you look at the morbidity and mortality risks of being underweight, this would make a lot more sense. The risks of being underweight are acute and profound, and rise precipitously with dropping BMI. In fact, the risks start accelerating below at BMI of 21 and exceed that of people with Class II obesity. Below 18.5 they exceed that of Class III obesity and rise dramatically.
Here is a fairly sound review that is easily understood and available at no charge
Nuttall, Frank Q. "Body Mass Index: Obesity, BMI, and Health: A Critical Review." Nutrition today 50.3 (2015): 117-128.
Nice! You're the first person on MFP I've encountered who explained to me why people may worry more for the one-pound-underweight person instead of the five-pounds-overweight person. Thanks the link! It was a good read.
However, I don't see where in the link it supported that a BMI under *21* had health risks greatly exceeding that of people with Class II obesity, enough to warrant worry. The focus and the conclusion written is that "being a bit overweight (preobese?) as determined by BMI may not be so bad." The journal writer does link an EPIC Observational Study about diabetes where a lower BMI was associated with a higher risk, but as was similar in other linked studies looking at BMI (like the General and Abdominal Adiposity and Risk of Death in Europe study), "circumference affected the mortality rate negatively" and lifestyle choices seemed to be another important factor. In other words, what I'm seeing being concluded is that from both ends of the BMI, the risks may not necessarily be something to be deeply concerned with when other factors, especially waist circumference, are taken into account.
The BMI <21 comes from several other studies that you can look up, in particular a recent review by a Korean group and another in Europe concluded the same thing. They controlled for preexisting illnesses, turns out opportunistic infections are aserious problem, followed by heart failure. Finding citations on my phone is a major pita so i only linked the free to read review.
If you search for BMI / morbidity and look at the graphs, you should see the dramatic curve/relative risk though. It's a super high tail for underweight , the curve rises fairly modestly throgh overweight and doesn't really take off until you pass grade III , largely because most of the illnesses of obesity are long term issues rather than acute.
I suspect the reason the morbidity trail starts growing at 21 is that you start seeing the effects for people who have larger frames and for whom low range BMI is not good experiencing illness. Just like many people say they look overweight at a BMI of 23, others may be quite gaunt at 20.1 -
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."
Waist to HEIGHT, mousepotato, not just waist to hip. When you are a slender build, waist to hip doesn't really work well. Waist to height should work. My waist to hip ratio is never *great* because I'm built pretty much straight up and down. The sleeker built you are, the worse this ratio will look.
That was in response to those who were advocating waist to hip over BMI. I'm good on waist to height although it doesn't take a lot of added pounds to cross that threshold as well! I'm about 5'3.5" and I had a 32" waist at 140 pounds. I seem to lose proportionally, so my WHR is always .82, regardless of my actual weight or body fat percentage. I have a BMI of 20.5 and I think my body fat is about 22%, but I've still got that.82 waist to hip ratio!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.
If you look at the morbidity and mortality risks of being underweight, this would make a lot more sense. The risks of being underweight are acute and profound, and rise precipitously with dropping BMI. In fact, the risks start accelerating below at BMI of 21 and exceed that of people with Class II obesity. Below 18.5 they exceed that of Class III obesity and rise dramatically.
Here is a fairly sound review that is easily understood and available at no charge
Nuttall, Frank Q. "Body Mass Index: Obesity, BMI, and Health: A Critical Review." Nutrition today 50.3 (2015): 117-128.
Nice! You're the first person on MFP I've encountered who explained to me why people may worry more for the one-pound-underweight person instead of the five-pounds-overweight person. Thanks the link! It was a good read.
However, I don't see where in the link it supported that a BMI under *21* had health risks greatly exceeding that of people with Class II obesity, enough to warrant worry. The focus and the conclusion written is that "being a bit overweight (preobese?) as determined by BMI may not be so bad." The journal writer does link an EPIC Observational Study about diabetes where a lower BMI was associated with a higher risk, but as was similar in other linked studies looking at BMI (like the General and Abdominal Adiposity and Risk of Death in Europe study), "circumference affected the mortality rate negatively" and lifestyle choices seemed to be another important factor. In other words, what I'm seeing being concluded is that from both ends of the BMI, the risks may not necessarily be something to be deeply concerned with when other factors, especially waist circumference, are taken into account.
The BMI <21 comes from several other studies that you can look up, in particular a recent review by a Korean group and another in Europe concluded the same thing. They controlled for preexisting illnesses, turns out opportunistic infections are aserious problem, followed by heart failure. Finding citations on my phone is a major pita so i only linked the free to read review.
If you search for BMI / morbidity and look at the graphs, you should see the dramatic curve/relative risk though. It's a super high tail for underweight , the curve rises fairly modestly throgh overweight and doesn't really take off until you pass grade III , largely because most of the illnesses of obesity are long term issues rather than acute.
I suspect the reason the morbidity trail starts growing at 21 is that you start seeing the effects for people who have larger frames and for whom low range BMI is not good experiencing illness. Just like many people say they look overweight at a BMI of 23, others may be quite gaunt at 20.
I suspect many of those with very low BMI's at a young age have little issue but that as their age goes up and they don't gain fat they may have other issues that are underlying the low BMI but not diagnosed. BF% should naturally gravitate up as we age and more fat deposits within the muscle and on problem areas, which should cause slight increases in weight and BMI as we age. Those who fail to gain a bit of weight are likely malnourished as well. I would like to see follow ups to determine the mechanisms of the mortality rate increase so we can see what is really going on.1 -
Mouse_Potato wrote: »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."
Waist to HEIGHT, mousepotato, not just waist to hip. When you are a slender build, waist to hip doesn't really work well. Waist to height should work. My waist to hip ratio is never *great* because I'm built pretty much straight up and down. The sleeker built you are, the worse this ratio will look.
That was in response to those who were advocating waist to hip over BMI. I'm good on waist to height although it doesn't take a lot of added pounds to cross that threshold as well! I'm about 5'3.5" and I had a 32" waist at 140 pounds. I seem to lose proportionally, so my WHR is always .82, regardless of my actual weight or body fat percentage. I have a BMI of 20.5 and I think my body fat is about 22%, but I've still got that.82 waist to hip ratio!
I'm similar, and was always paranoid that I had more visceral fat as a result, even though I suspected it was just due to build (lots of people will insist that if your w-h ratio is off that's a risk factor, no matter why it is). I had a DEXA when I was around 145 (and a follow up at about 130 as part of the same purchase), and was relieved that my visceral fat wasn't an issue even when I was a bit over and certainly not at 130--it really was build and the fact that my hips are relatively narrow and I'm short waisted, proportionally.
My insurance company has a wellness check you can go through (it doesn't affect the cost, though), and it will use the waist measurement (I think waist to height) as a test if you are in the BMI overweight (25-29) zone, and if the waist is okay it doesn't give weight as a problem within that range.1 -
when I was 172 lbs last year I was "overweight" people at work were shocked. when I was 182 2 years ago I was borderline obese once again people at work couldn't believe it.
Currently 163 I score a 24 BMI at 5'8" last year and the year before it said I was 5' 9" (must have shrunk an inch since last year or at least a half inch to lose the round up option)
with that weight loss came strength loss even though I train 5x a week. Do I think the BMI scale has value...sure. would I bank on it NSM.1 -
lemurcat12 wrote: »Mouse_Potato wrote: »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."
Waist to HEIGHT, mousepotato, not just waist to hip. When you are a slender build, waist to hip doesn't really work well. Waist to height should work. My waist to hip ratio is never *great* because I'm built pretty much straight up and down. The sleeker built you are, the worse this ratio will look.
That was in response to those who were advocating waist to hip over BMI. I'm good on waist to height although it doesn't take a lot of added pounds to cross that threshold as well! I'm about 5'3.5" and I had a 32" waist at 140 pounds. I seem to lose proportionally, so my WHR is always .82, regardless of my actual weight or body fat percentage. I have a BMI of 20.5 and I think my body fat is about 22%, but I've still got that.82 waist to hip ratio!
I'm similar, and was always paranoid that I had more visceral fat as a result, even though I suspected it was just due to build (lots of people will insist that if your w-h ratio is off that's a risk factor, no matter why it is). I had a DEXA when I was around 145 (and a follow up at about 130 as part of the same purchase), and was relieved that my visceral fat wasn't an issue even when I was a bit over and certainly not at 130--it really was build and the fact that my hips are relatively narrow and I'm short waisted, proportionally.
My insurance company has a wellness check you can go through (it doesn't affect the cost, though), and it will use the waist measurement (I think waist to height) as a test if you are in the BMI overweight (25-29) zone, and if the waist is okay it doesn't give weight as a problem within that range.
Short-waisted is my other issue as well. It's 28" now and was 27" when I was in high school, but I weighed less than 100 pounds at the time. I'm not sure it is possible anymore. I simply don't have the bone structure to get a tiny waist and my hips never seem to grow much. They were 39" at my heaviest. Like Robin said - straight up and down!0 -
Wheelhouse15 wrote: »trigden1991 wrote: »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.
I am "obese" according to the BMI charts however I am under 15% bodyfat. The charts aren't good for people who are athletic, undertake resistance training, are very short or very tall.
What are you stats? You certainly don't look like you would be obese from you PP.
I'm 6'3 and around 240lbs at sub 15% bodyfat. The system is flawed for a large majority of the population.1 -
trigden1991 wrote: »Wheelhouse15 wrote: »trigden1991 wrote: »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.
I am "obese" according to the BMI charts however I am under 15% bodyfat. The charts aren't good for people who are athletic, undertake resistance training, are very short or very tall.
What are you stats? You certainly don't look like you would be obese from you PP.
I'm 6'3 and around 240lbs at sub 15% bodyfat. The system is flawed for a large majority of the population.
Actually, that makes sense since BMI becomes less accurate for taller people. BMI would be much more accurate for you if it was at height^2.5.1 -
trigden1991 wrote: »Wheelhouse15 wrote: »trigden1991 wrote: »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.
I am "obese" according to the BMI charts however I am under 15% bodyfat. The charts aren't good for people who are athletic, undertake resistance training, are very short or very tall.
What are you stats? You certainly don't look like you would be obese from you PP.
I'm 6'3 and around 240lbs at sub 15% bodyfat. The system is flawed for a large majority of the population.
Correct me If I'm wrong but 6'3 at 240 pounds and sub 15% is not a large majority of the population, Or any majority for that matter.9 -
stevencloser wrote: »trigden1991 wrote: »Wheelhouse15 wrote: »trigden1991 wrote: »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.
I am "obese" according to the BMI charts however I am under 15% bodyfat. The charts aren't good for people who are athletic, undertake resistance training, are very short or very tall.
What are you stats? You certainly don't look like you would be obese from you PP.
I'm 6'3 and around 240lbs at sub 15% bodyfat. The system is flawed for a large majority of the population.
Correct me If I'm wrong but 6'3 at 240 pounds and sub 15% is not a large majority of the population, Or any majority for that matter.
Maybe if we restrict our population to NFL TEs?
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Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.7 -
Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Absolutely agree, that's something that's hard to do and kudos are earned here!0 -
In my experience, those who can't use BMI accurately (because they have such a high percentage of muscle) are NOT the ones saying it's useless. Usually those saying it's totally useless are those making excuses. Like being "big boned" in the 80's... Whatever. BMI has such a broad range within each category, it's bound to fit most people6
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Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Thank you for your kind words.
@stevencloser I wasn't overly concise in what I wrote. I wasn't referring to myself as a majority of the population. In my previous post I mentioned that the BMI scale falls apart when you are very short, tall or muscled.
@Wheelhouse15 Thanks. Lots of hard work!0 -
trigden1991 wrote: »Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Thank you for your kind words.
@stevencloser I wasn't overly concise in what I wrote. I wasn't referring to myself as a majority of the population. In my previous post I mentioned that the BMI scale falls apart when you are very short, tall or muscled.
@Wheelhouse15 Thanks. Lots of hard work!
But by definition, being very short or very tall falls outside the average and won't be the majority of people. Very muscled vs. extremely non-muscular the same.
For example, you at 6'3'' are taller than 98% of the US population your age.
https://www2.census.gov/library/publications/2010/compendia/statab/130ed/tables/11s0205.pdf4 -
stevencloser wrote: »trigden1991 wrote: »Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Thank you for your kind words.
@stevencloser I wasn't overly concise in what I wrote. I wasn't referring to myself as a majority of the population. In my previous post I mentioned that the BMI scale falls apart when you are very short, tall or muscled.
@Wheelhouse15 Thanks. Lots of hard work!
But by definition, being very short or very tall falls outside the average and won't be the majority of people. Very muscled vs. extremely non-muscular the same.
For example, you at 6'3'' are taller than 98% of the US population your age.
https://www2.census.gov/library/publications/2010/compendia/statab/130ed/tables/11s0205.pdf
Very valid point. I forget that the gym population is not representative of the wider population.4 -
trigden1991 wrote: »stevencloser wrote: »trigden1991 wrote: »Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Thank you for your kind words.
@stevencloser I wasn't overly concise in what I wrote. I wasn't referring to myself as a majority of the population. In my previous post I mentioned that the BMI scale falls apart when you are very short, tall or muscled.
@Wheelhouse15 Thanks. Lots of hard work!
But by definition, being very short or very tall falls outside the average and won't be the majority of people. Very muscled vs. extremely non-muscular the same.
For example, you at 6'3'' are taller than 98% of the US population your age.
https://www2.census.gov/library/publications/2010/compendia/statab/130ed/tables/11s0205.pdf
Very valid point. I forget that the gym population is not representative of the wider population.
Actually, that's very common. When I look at my lifts compared to the monsters at the gym I forget that I'm pushing more weight than 98% of people. We tend to see ourselves in comparison to our immediate reference group rather than to the population at large.
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Wheelhouse15 wrote: »trigden1991 wrote: »stevencloser wrote: »trigden1991 wrote: »Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Thank you for your kind words.
@stevencloser I wasn't overly concise in what I wrote. I wasn't referring to myself as a majority of the population. In my previous post I mentioned that the BMI scale falls apart when you are very short, tall or muscled.
@Wheelhouse15 Thanks. Lots of hard work!
But by definition, being very short or very tall falls outside the average and won't be the majority of people. Very muscled vs. extremely non-muscular the same.
For example, you at 6'3'' are taller than 98% of the US population your age.
https://www2.census.gov/library/publications/2010/compendia/statab/130ed/tables/11s0205.pdf
Very valid point. I forget that the gym population is not representative of the wider population.
Actually, that's very common. When I look at my lifts compared to the monsters at the gym I forget that I'm pushing more weight than 98% of people. We tend to see ourselves in comparison to our immediate reference group rather than to the population at large.
Absolutely, maybe I should find some average height overweight friends so I can skew my perceptions back to "normal".0 -
trigden1991 wrote: »stevencloser wrote: »trigden1991 wrote: »Yea, 6'3, 240 and sub 15 is a person you notice. Like "damn, that's a beast right there!" I sure as hell don't say that all that often. Far from any majority. Lol.
Basically, how many times per day do you look at someone and think they are a beast? That's how many oitliers there are...
Kinda joking but kinda serious. Either way, well done. You are a beast!
All serious. No sarcasm.
Thank you for your kind words.
@stevencloser I wasn't overly concise in what I wrote. I wasn't referring to myself as a majority of the population. In my previous post I mentioned that the BMI scale falls apart when you are very short, tall or muscled.
@Wheelhouse15 Thanks. Lots of hard work!
But by definition, being very short or very tall falls outside the average and won't be the majority of people. Very muscled vs. extremely non-muscular the same.
For example, you at 6'3'' are taller than 98% of the US population your age.
https://www2.census.gov/library/publications/2010/compendia/statab/130ed/tables/11s0205.pdf
Very valid point. I forget that the gym population is not representative of the wider population.
We run into this issue in the military as the Physical Readiness Test (PRT) guidelines are based on BMI. If you fail BMI standards, then you get measured with calipers to determine body fat %. Of course the military, similar to the gym population represents the top 3% of the US fitness determinants, so this is essentially a population of outliers.1 -
trigden1991 wrote: »Wheelhouse15 wrote: »trigden1991 wrote: »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.
I am "obese" according to the BMI charts however I am under 15% bodyfat. The charts aren't good for people who are athletic, undertake resistance training, are very short or very tall.
What are you stats? You certainly don't look like you would be obese from you PP.
I'm 6'3 and around 240lbs at sub 15% bodyfat. The system is flawed for a large majority of the population.
Great job. At your height, weight and BF% you are approaching major college/NFL linebacker size and bodyfat. That area is pretty rare air. You are part of the 10% or so where BMI doesn't work. It does work for the large majority of the population.2
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