Small frame + low BMI
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Small frame + low BMI
Hi guys,
For a start I stand at 1.70m tall but I weigh a pathetic 50kg. That would give my BMI figure of about 17.3 only which makes me way underweight. I've tried all means to gain weight but I never succeeded all along. I eat a lot and I enjoy all kinds of food unhealthy or healthy and my GP points it to genetic factors that I cant put on weight.
I've done a search before in this forum but the threads were quite sometime ago and I wonder if anyone has any idea if this would affect me from passing the class 1 medical? If of any interest I have passed the class 2 medical before and I'm wondering if there are any issues in weight or BMI that are not in class 2 but have some requirements in class 1.
Thanks!
For a start I stand at 1.70m tall but I weigh a pathetic 50kg. That would give my BMI figure of about 17.3 only which makes me way underweight. I've tried all means to gain weight but I never succeeded all along. I eat a lot and I enjoy all kinds of food unhealthy or healthy and my GP points it to genetic factors that I cant put on weight.
I've done a search before in this forum but the threads were quite sometime ago and I wonder if anyone has any idea if this would affect me from passing the class 1 medical? If of any interest I have passed the class 2 medical before and I'm wondering if there are any issues in weight or BMI that are not in class 2 but have some requirements in class 1.
Thanks!
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Hi,
I don't know if you'd pass with that BMI but I would really like to know...my BMI is low too (18 on a good day!). I have an awful feeling that they'd want it to be above 18, however it seems unfair as the maximum is in the 30's! ie you can be overweight but not under? Let me know if you get an answer
Helen:-)
I don't know if you'd pass with that BMI but I would really like to know...my BMI is low too (18 on a good day!). I have an awful feeling that they'd want it to be above 18, however it seems unfair as the maximum is in the 30's! ie you can be overweight but not under? Let me know if you get an answer
Helen:-)
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Make sure you have some rocks in your pockets when you get on the scales. If you are otherwise fit and healthy (and don't have some eating disorder) then don't worry about it. BMI covers a range and is really based upon large populations, some healthy people will be outside the middle bit of the range, that's statistics for you.
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Thanks for the reply. I'm sure I'm healthy I eat and sleep well and I exercise regularly. The only problem is that no matter how much I eat I can't gain weight and if I eat lesser than usual I tend to lose some weight which is very difficult to gain back as well.
I'm going for the class 1 in a few days time and I'll let you know if I pass.
I'm going for the class 1 in a few days time and I'll let you know if I pass.
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If you don't look too skinny, are able to perform normal exercises, eat normally & healthy, don't worry.
The BMI seems to be the holy grail of weight watching today but my mathematical background tells me there's something wrong with it. The BMI calculation uses the square of your length (length * length) but simple math tells us that the volume of a body, and therefore its weight, is proportional to the third power of your length (length * length * length), all other proportions being equal.
In other words, assuming equal proportions, should a person being 2 meters tall be allowed to be twice as heavy, four times as heavy or eight times as heavy as a person being 1 meters tall? I think eight times, since the person is twice as big, in all three dimensions. But the BMI calculations only allows four times as heavy.
Now for an average person size (about 1.80 to 1.90) it won't matter that much (that's what the BMI overweight/underweight numbers are calibrated for), but for shorter people, the current BMI calculations almost by default puts them into the "underweight" category, and larger people almost by default are "overweight".
Now I only need to convince the whole world the BMI calculation is wrong...
Discussion on BMI and its general value of diagnosing individuals (which it was never intended for) at Wikipedia: http://en.wikipedia.org/wiki/Body_mass_index
Read the "discussion" page on the Wikipedia too. I especially like the following quote:
The BMI seems to be the holy grail of weight watching today but my mathematical background tells me there's something wrong with it. The BMI calculation uses the square of your length (length * length) but simple math tells us that the volume of a body, and therefore its weight, is proportional to the third power of your length (length * length * length), all other proportions being equal.
In other words, assuming equal proportions, should a person being 2 meters tall be allowed to be twice as heavy, four times as heavy or eight times as heavy as a person being 1 meters tall? I think eight times, since the person is twice as big, in all three dimensions. But the BMI calculations only allows four times as heavy.
Now for an average person size (about 1.80 to 1.90) it won't matter that much (that's what the BMI overweight/underweight numbers are calibrated for), but for shorter people, the current BMI calculations almost by default puts them into the "underweight" category, and larger people almost by default are "overweight".
Now I only need to convince the whole world the BMI calculation is wrong...
Discussion on BMI and its general value of diagnosing individuals (which it was never intended for) at Wikipedia: http://en.wikipedia.org/wiki/Body_mass_index
Read the "discussion" page on the Wikipedia too. I especially like the following quote:
At the following url is a fit calculation that comes up with an exponent of 2.59 (about half way between square and cube)
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dream747, I now see you come from 'Tropical Equator' so what ethnic group are you from? I am guessing you are from Asia.
Work in the past few years has shown that 'normal' BMI is different in Asians. The researchers tended to concentrate at the dividing line between 'normal' and 'overweight', which has been brought down in asian populations to perhaps around the 23. The lower limit of 'normal' is now said in asians by WHO to be around 18.5, but I suspect that if further work was done on that figure it might drop a bit too. Just an educated guess.
But anyway, just showing that what they thought was 'normal' BMI as little as 5 years ago is now considered wrong. It's really not as important as you think it is. Body fat %age and distribution is what matters in my opinion, problem with that is it's not as easy to measure accurately in a doctor's surgery as BMI, so people don't bother. That will change.....
Work in the past few years has shown that 'normal' BMI is different in Asians. The researchers tended to concentrate at the dividing line between 'normal' and 'overweight', which has been brought down in asian populations to perhaps around the 23. The lower limit of 'normal' is now said in asians by WHO to be around 18.5, but I suspect that if further work was done on that figure it might drop a bit too. Just an educated guess.
But anyway, just showing that what they thought was 'normal' BMI as little as 5 years ago is now considered wrong. It's really not as important as you think it is. Body fat %age and distribution is what matters in my opinion, problem with that is it's not as easy to measure accurately in a doctor's surgery as BMI, so people don't bother. That will change.....
It is changing already, we are now urged to take into account waist circumference, as well as BMI, as we are told that this is a more reliable predictor of illness.
http://guidance.nice.org.uk/CG43/nic...e/word/English
It's more to do with where the fat is, rather than how much there is.
http://guidance.nice.org.uk/CG43/nic...e/word/English
It's more to do with where the fat is, rather than how much there is.
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Yes, as I said, distribution is important. Waist measurement is a good indicator. For men it can be used to directly calculate body fat percentage. For women you also need to include the hip measurement, NICE hasn't caught on to that yet 
You also need to measure a bony part of the body like the wrist to get some input on bone mass. The major change which is required is to use this to measure body fat and to use that instead of BMI, NICE hasn't got to grips with that either. This will only be a rough estimate as you don't tend to have the complex equipment in a surgery to accurately measure body fat. But even as rough as it is, it is better than BMI for individuals. All in my opinion of course which is worth what you paid for it
You also need to measure a bony part of the body like the wrist to get some input on bone mass. The major change which is required is to use this to measure body fat and to use that instead of BMI, NICE hasn't got to grips with that either. This will only be a rough estimate as you don't tend to have the complex equipment in a surgery to accurately measure body fat. But even as rough as it is, it is better than BMI for individuals. All in my opinion of course which is worth what you paid for it
NICE hasn't caught on to that yet
I'm just sorry to all the people I've been (falsely) calling fatty all these years
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Where have they caught on? I haven't seen it, happy to be corrected.
It's not hard to work out, even in primary care. It's a simple calculation that could be done in a web page on your pc. Enter height, weight, waist, hip, wrist (or neck or whatever is used in the chosen formula) and you get a number accurate to within a few percent.
And anyway, what's wrong with taking a pop at NICE
It's not hard to work out, even in primary care. It's a simple calculation that could be done in a web page on your pc. Enter height, weight, waist, hip, wrist (or neck or whatever is used in the chosen formula) and you get a number accurate to within a few percent.
And anyway, what's wrong with taking a pop at NICE
Nothing at all, some people have made a career out of it
I can see nothing at all in their published stuff relating to identification of at risk individuals, other than clinical judgement, (whatever that is!), BMI, and waist measurement, so I guess you could assume that they havn't caught on. (Sorry to be coy, but they would have considered other measures too.)
I'm making a few assumptions here, but I guess what NICE are trying to do, are marry up the available interventions, (and I have to say, the evidence for some of these is questionable), with a more accurate method of identifying at risk individuals.
Primary care foot soldiers are in an ideal position to deliver this, as we, generally, are very accessible to our population, and are have the experience of delivering systematic care through a patients lifetime.
On a practical note, measuring hips and wrists probably won't happen, unless we could demonstrate real health benefit. It's an uphill struggle gaining the waist measurements- I'm sure you know the pressures.
I can see nothing at all in their published stuff relating to identification of at risk individuals, other than clinical judgement, (whatever that is!), BMI, and waist measurement, so I guess you could assume that they havn't caught on. (Sorry to be coy, but they would have considered other measures too.)
I'm making a few assumptions here, but I guess what NICE are trying to do, are marry up the available interventions, (and I have to say, the evidence for some of these is questionable), with a more accurate method of identifying at risk individuals.
Primary care foot soldiers are in an ideal position to deliver this, as we, generally, are very accessible to our population, and are have the experience of delivering systematic care through a patients lifetime.
On a practical note, measuring hips and wrists probably won't happen, unless we could demonstrate real health benefit. It's an uphill struggle gaining the waist measurements- I'm sure you know the pressures.
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Originally Posted by gingernut
On a practical note, measuring hips and wrists probably won't happen, unless we could demonstrate real health benefit.
Waist-to-hip ratio shows a graded and highly significant association with myocardial infarction risk worldwide. Redefinition of obesity based on waist-to-hip ratio instead of BMI increases the estimate of myocardial infarction attributable to obesity in most ethnic groups.
Yusuf et al.
The Lancet 2005; 366:1640-1649
You would be better off working on your patient's waist:hip than working on their exercise habits! It will come through, just needs NICE to get round to doing something about it, I am sure they are aware of it.
Yeh, interesting to see waist/hip ratio is three times as accurate as BMI alone.
But we are addressing waist measurement, (not hip).
Do you reckon doing both would make that much difference?
But we are addressing waist measurement, (not hip).
Do you reckon doing both would make that much difference?
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They all seem to have got mixed up in the discussion.
I think there was an analysis done on the INTER-HEART data which determined that waist measurement alone was not as good as waist:hip. Will pull the paper tomorrow as I have forgotten the gory details. This is of course strictly only for myocardial infarction...
I think there was an analysis done on the INTER-HEART data which determined that waist measurement alone was not as good as waist:hip. Will pull the paper tomorrow as I have forgotten the gory details. This is of course strictly only for myocardial infarction...
Thanks Slim, I am aware of the big studies.
What I need to know, is if it's worth dropping something, (take your choice: smoking cessation, hip relplacements, air ambulances), to spend extra time measuring hips, for a net health gain?
(If "Clinical Judgement" and BMI is the initial pointer, then we'll have to measure a lot of hips)
Sorry, haven't got the answer, and I'm not sure that the big studies do either
Which is why, perhaps, I'm (over)relying on N.I.C.E.
What I need to know, is if it's worth dropping something, (take your choice: smoking cessation, hip relplacements, air ambulances), to spend extra time measuring hips, for a net health gain?
(If "Clinical Judgement" and BMI is the initial pointer, then we'll have to measure a lot of hips)
Sorry, haven't got the answer, and I'm not sure that the big studies do either
Which is why, perhaps, I'm (over)relying on N.I.C.E.
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The interheart study does in fact give you a clue to the risk factors you should be concentrating on in primary care - for myocardial infarction
Top is hyperlipidemia as measured by raised ApoB/ApoA1 ratio.
smoking, only a few ciggies a day is enough
psychosocial factors (which is probably a bit difficult to quantify)
Body fat, essentially abdominal obesity which is quantified using waist:hip ratio - not BMI
So I guess you could say the rest are less important for you to concentrate on. Other factors in order of importantce are
hypertension - yes comes in lower than abdominal obesity, but self reported so possibly should be higher.
friut and veg (protective)
exercise (protective)
diabetes (risk, and probably should be higher than the study suggests as lots of diabetics are undiagnosed, but that's just me spouting again )
alcohol which is again protective.
I sympathise with primary care providers and their patients who are waiting for NICE to give guidance They will get round to it, I guess it takes time to work out how much the guidance will cost.........
Also, as I said, this only looks at myocardial infarction. But to the subject of the thread. If BMI (the initial question which spawned this discussion) is a waste of time for predicting MI, could you assume it's a waste of time for the rest? Well, I reckon so, and there I go spouting again.....
Lancet 2004; 364:937-952 Yusuf et al
Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study
Top is hyperlipidemia as measured by raised ApoB/ApoA1 ratio.
smoking, only a few ciggies a day is enough
psychosocial factors (which is probably a bit difficult to quantify)
Body fat, essentially abdominal obesity which is quantified using waist:hip ratio - not BMI
So I guess you could say the rest are less important for you to concentrate on. Other factors in order of importantce are
hypertension - yes comes in lower than abdominal obesity, but self reported so possibly should be higher.
friut and veg (protective)
exercise (protective)
diabetes (risk, and probably should be higher than the study suggests as lots of diabetics are undiagnosed, but that's just me spouting again )
alcohol which is again protective.
I sympathise with primary care providers and their patients who are waiting for NICE to give guidance
They will get round to it, I guess it takes time to work out how much the guidance will cost......... Also, as I said, this only looks at myocardial infarction. But to the subject of the thread. If BMI (the initial question which spawned this discussion) is a waste of time for predicting MI, could you assume it's a waste of time for the rest? Well, I reckon so, and there I go spouting again.....
Lancet 2004; 364:937-952 Yusuf et al
Effect of potentially modifiable risk factors associated with myocardial infarction in 52 countries (the INTERHEART study): case-control study
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Thanks people for the inputs.
I've gone for the class 1 and apparently I had some unexpected problems which may pose a risk in me not being able to clear it.
I have a heart condition... called something like DRBBB or something like that where in my heart the (current)? whe passes through takes a longer time to travel than that on the left when both should reach at the same time. There is a possibility that I might have to see a cardiologist.
Next my small build - I guess small lungs as well.. I couldn't pass the spirometry test. The results should I have a mild constriction in my lungs. The DME said that he's confident I have nothing wrong with my lungs just that I'm small built therefore smaller lungs hence smaller air capacity than most people but don't know how the authorities would think though.
Though the doctor said that height and weight or BMI is not a factor or at least being underweight is not. That's for the part of the world I'm in.
I've gone for the class 1 and apparently I had some unexpected problems which may pose a risk in me not being able to clear it.
I have a heart condition... called something like DRBBB or something like that where in my heart the (current)? whe passes through takes a longer time to travel than that on the left when both should reach at the same time. There is a possibility that I might have to see a cardiologist.
Next my small build - I guess small lungs as well.. I couldn't pass the spirometry test. The results should I have a mild constriction in my lungs. The DME said that he's confident I have nothing wrong with my lungs just that I'm small built therefore smaller lungs hence smaller air capacity than most people but don't know how the authorities would think though.
Though the doctor said that height and weight or BMI is not a factor or at least being underweight is not. That's for the part of the world I'm in.
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That's a bit of a nuisance. Probably worth looking at that in a little more detail and go see a cardiologist. A bit of RBBB could almost be considered a 'normal variant', loads of us have it without knowing, and if the doc who saw you said your lungs are fine then you should be OK.
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Slim_slag,
Was told by the DME that chances are that the authorities would require me to see a cardiologist as that condition can't accurately ascertain that my heart is perfectly normal.
Regarding the lungs, he told me that it could be hard to pass. I'm not sure but there's nothing I can do... I'm small in size so my lungs can't be anywhere big!
Was told by the DME that chances are that the authorities would require me to see a cardiologist as that condition can't accurately ascertain that my heart is perfectly normal.
Regarding the lungs, he told me that it could be hard to pass. I'm not sure but there's nothing I can do... I'm small in size so my lungs can't be anywhere big!