Quite a few years ago I worked in the same office as a guy with BMI 40+ who had sleep apnoea and used to fall asleep at his desk.
It “didn’t affect his work” apparently. :-)
I don’t know what particular potential incapacitation issues the CAA is most worried about with high BMI pilots. My own concerns about sharing a cockpit are that in an emergency they aren’t going anywhere very rapidly, and if they are hurt/unconscious then you can’t get past them in the confined space of a light aircraft cockpit. I do not like to sit in the left seat of a single-door aircraft unless the person next to me is small enough to manhandle out of the door in an emergency.
MedEwok wrote:
So basically, the risk of suicide, accidents or neurological diseases killing you is the lowest at BMI ranges 24 to 27 kg/m², for most other causes of death it’s lowest between 21 to 25 kg/m². So being at the higher end of the normal range 24 to 25 kg/m² ish seems to be a “sweet spot” for low mortality.
So with a BMI around 26 and pretty perfect (low) blood pressure it sounds like I’m good for another few years, LOL !
In any case: IMHO it doesn’t matter how long you live – what matters is how well you live and how much fun you have doing so.
MedEwok wrote:
Regarding @Mooney_Driver s question earlier whetee being slightly overweight increases life expectancy: for some causes of death yes, for others no.
Thank you @MedEwok!
kwlf wrote:
the environments we find ourselves in can be more or less enabling when it comes to eating healthily
Absolutely. I found the night shifts, as much as I loved them, to be toxic when it comes to that subject. Even with less calories eaten, I would gain weight.
kwlf wrote:
Some of my other bugbears are two for one deals in supermarkets.
And while you are at it, supersize meals in food outlets. Or all you can eat buffets, even though they do have advantages for dieters, as you can put your food together as you wish and leave out things you know you should not eat. For that reason, strangely, I never gained weight but actually lost some regularly when staying at an All Inclusive place.
kwlf wrote:
I have never understood why a tiny 35g packet of crisps costs only slightly less than a 150g packet
Logistics mostly. A package for a small packet costs pretty much the same than for a 150g pack and also transport and shelfspace logistics are much higher per gram so to speak. Also, the 35 g packs usually are intended for things like automats or kiosks, which in general are more expensive. In supermarkets, 150 to 300 g packs are much more common.
MikeWhiskey wrote:
So, why are they still referring to BMI, in my view analyzing blood data (and whathever more) would make more sense?
You are talking of the Swiss FOCA? The 35 BMI limit is an EASA hard limit for class II medicals. Consequently, when the AME’s enter the weight, that letter will get triggered automatically. The thing is that if you get two exams in a row with a BMI like that, they will send you to a cardiologe (on your cost of course) to check you out and possibly impose other restrictions. Why EASA chose to take over this restriction? Probably because it is an easy figure to remember and implement. My AME always checks my blood too btw.
Graham wrote:
I don’t know what particular potential incapacitation issues the CAA is most worried about with high BMI pilots.
From what I was told it is primarily cardio-vascular diseases they take BMI as a first warning sign for. In general, in Aviation Medicine, the primary goal is to avoid pilots incapacitation of any sort, particularly with single pilot crews. Hence, diabetic persons will also be grounded or at the very least be restricted to carrying a safety pilot. Sleep apnoea e.t.c. are clearly also a very serious condition for this.
On the latter, I’ve had a case of those close to me which got treated successfully. That person was perfectly normal in weight but had restrictions in her nasal tract, which lead to massive snoring. Her HNO sorted her out. From what I gathered from that case, sleep apnoe has to do with a malfunctioning breathing apperatus. Clearly, overweight people are prone to this but not only them and by far not all of them.
“normal range was somehow objectively defined as the lower and upper bound of what a ‘not skinny and not fat’ person might weigh.”
There is also variation in bone density, musculature, and shape.
Mechanical stress increases bone density. Exercise against force increases muscle size. Increased mass with no increase in height or fat.
An interesting comparison is chest, waist, hip measurements.
I understand an electrical conductivity measurement between feet can give an indication of body fat.
Sleep apnoea is very strongly correlated with road traffic accidents. I always thought it was partly due to impairing decision-making ability / decreased alertness, but most of the papers talk about simply falling asleep at the wheel. I don’t know whether there are many instances of recreational pilots falling asleep?
It’s astounding that BMI is still in use. It was invented in the 1840s (iirc) when the world was a very different place and most people were seriously undernourished. What looks “skinny” now would have looked overweight then. It also has a fundamental flaw that it uses the square of height, not the cube, meaning that it gives a high figure for tall people and a low one for short people. I think the health business just glommed onto it ~15 years ago and now it has become an obsession.
Honestly you don’t need some fancy math to see when someone has a bit of extra weight. I just got fed up with the way it looked and felt – not to mention it was getting in the way of aviation – and decided a couple of years ago to try and lose 30kg. I managed about 25, though a few have crept back on since. It wasn’t exactly hard, though it did take willpower. And I didn’t lose friends – just as well, because I don’t have many to begin with. I did it by eating a very low calorie diet (target 500/day, actual probably more like 700) during the week. At weekends I ate and drank more or less normally, though of course trying to avoid stuff that I would just have to undo the following week. So I could still have dinner etc with friends.
It has, needless to say, made a big difference to the way I feel, and look too. My back problems which were beginning to get seriously in the way have mostly disappeared.
Still, my BMI is now around 29. Ideally it would be maybe 27. If it got to 20, which is the definition of underweight, people would stop me in the street to feed me.
johnh wrote:
It also has a fundamental flaw that it uses the square of height, not the cube, meaning that it gives a high figure for tall people and a low one for short people.
People don’t scale linearly as they grow taller so the ideal exponent would be neither 2 nor 3, but somewhere in between. I agree it’s a crude measure, but medicine is not like aeronautical engineering where you can design and build a wing and predict when it will snap to within 1%. Perhaps the actuaries care if someone is 24.5 v 25.5, but in a hospital setting if a patient has a bmi of 38 it makes no practical difference if it should have been 37 or 39.
A better scale would include skin fold, waist and hip measurements and electrical impedance measurements and probably factors like sex and ethnicity. And nobody would ever bother calculating it outside of research settings.
Well done with your weight loss. Not many people seem to manage to lose that much weight successfully.
MedEwok wrote:
So being at the higher end of the normal range 24 to 25 kg/m² ish seems to be a “sweet spot” for low mortality.
Damn it, I’m at 26!
I think the BMI is only good for a very basic “first order” analysis. As in: if ALL the information you have about somebody is height and mass, then sure, check their BMI. But I believe this picture is VASTLY incomplete to tell whether somebody is healthy or not.
There are plenty of TOFI people around: Thin on the Outside, Fat on the Inside, which is a much bigger risk than just being overweight but otherwise healthy.
It’s a bit like the Taylor Series of a mathematical function, for anybody who’s studied Calculus. If all the information you have about a function is its value at one point, and the value of its derivative at that point, than your “best approximation” of the curve is a straight line passing through that point with the slope at the point. Of course this approximation could be completely detached from reality.
kwlf wrote:
aeronautical engineering where you can design and build a wing and predict when it will snap to within 1%.
Well…
Aeronautical engineers like the general public thinking that they can actually do it… But if it were true you wouldn’t hear such loud cheers when this happens:
