dynamictiger wrote:I have to question the use of BMI even as a population tool. To apply it to an individual is laughable in the extreme. According to my BMI my doctor told me I should be 85kg. My response to him was that's very nice doctor...can you please tell me what happens when I turn 11.
I was so curious as to why this was so far out I researched into where it came from and discovered it was derived in Belgium before my country of birth was discovered. Logically this leads to a thought process with the logical conclusion of how could something invented in Europe where the winters are harsh and the population largely lived on turnips apply to a modern country where foods are varied and plentiful and winters comparatively mild (meaning we are more active etc).
For the same reason comparing 1926 to 2008 is verging on ridiculous. There was a depression on, people were unemployed and many missed meals etc. So what has that got to do with 2008?
Researchers do not just use the 25% currently favoured in Oz and many other countries. It is just a one-size-fits-all that is currently the focus of the popular media and, with them, us. Southern Italians may be just as well off with a higher BMI so some analysts would adjust for that.
I don't doubt that BMI is crude but it has the benefit of ease and cost. Every measure that anyone will come up with will be questionable as they are ALL a proxy for something else we are interested in. For example, the only perfect measure to predict the likely effect of current diet on levels of diabetes in the future will be to test everyone in twenty years time. Then we will never KNOW the future but by then the future has become the past and of no value to policy makers at this time. And, of course, even with, a better and costlier measuring stick that us only marginally better, analysts then still have to contend with other confounding variables. Sort of reduces the value of incrementally better measurement.
There is room to reconsider some of the things that we do use BMI as a proxy measure for. Waist to hip ratio is being used a lot now as an indicator of risk of coronary stress for example.