AN ALTERNATIVE TO BMI-IS IT RELIABLE?

Body Mass Index or more commonly known by its acronym BMI is considered a sacred cow which no one wants to question. It is supposed to make a value judgment regarding the status of health one enjoys and what dietary modifications are called for in rectifying any abnormalities reflected by the BMI value. Though it was evolved 150 years ago, many suggestions made from time to time were not acceptable to a vast majority of health pundits and medical community. One of the uncertainties about the reliability of BMI is that it does not differentiate between weight caused by fat and muscle with the possibility some normal persons may be bracketed as over weight while some unhealthy persons may be categorized as normal. Also questionable is the arbitrary figures adopted in different countries for classifying people a over weight and obese. Latest suggestion to modify calculation of BMI uses a different equation to factor the height more realistically into the calculation. How far the new formula will yield better and more accurate result remains to be seen. Here is a take on this new development.      

"Any system that tells people whether they are "normal", "underweight", "overweight" or "obese" is bound to be controversial, but one obvious weakness of the BMI is that it doesn't distinguish between fat and muscle.First devised by Adolphe Quetelet more than 150 years ago, BMI is calculated by taking your weight (in kilograms) and dividing it by your height squared (in metres). The body-mass index that you (and the National Health Service) count on to assess obesity is a bizarre measure... As a consequence of this ill-founded definition, millions of short people think they are thinner than they are, and millions of tall people think they are fatter.
    * Prof Trefethen's letter in full (third in list)
    * His explanation of his formula
But mathematician Nick Trefethen, Professor of Numerical Analysis at Oxford University, thinks that the old formula is wrong, as he explained in a letter to the Economist newspaper published earlier this month. He thinks that people have put too much trust in it in part because it looks so precise - like, say, Einstein's famous equation E=MC². "That's an equation of physics and it's really right. The BMI formula looks similar. It seems to have the same character but it doesn't reflect a precise truth about our world, it's an approximation to a very complicated reality," he told the BBC.
With that in mind he has proposed a new formula: 1.3 x weight, divided by height to the power 2.5".

No matter which equation is used human body is so diverse that it will be difficult to classify them based on any single formula. The extent of muscle and fat present in the body is difficult to be assessed and therefore BMI can at best be an approximation of the state of health of a person at any given time. In the case of fat too, quality and the location of this component will decide whether weight contributed by fat is good or bad. Under such an uncertain situation BMI is still a good reckoner or indicator regarding the health status of most people. Those with high BMI can always go for further diagnostic tests to decide whether they are healthy or not.    

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com

WEIGHT CONTROL IS NO MORE RELEVANT? IT SEEMS SO!

Overweight and obesity related health disorders are increasingly becoming common, especially among population in wealthy countries who have easy access to cheap but calorie and fat rich food products. Billions of dollars are being invested by consumers affected by these disorders for getting rid of excess weight and fat in the body to escape from the consequences of overweight, scientifically documented by many studies at the international level. While a majority of medical, nutritional and health experts feel that overweight is really dangerous, there is a small segment of scientific community which maintains that over weight people are not at greater risk of dying compared to normal weight persons. Here is a take on this conflicting views which can derail the current aggressive approach on obesity alleviation.

"It's a common medical refrain: Carrying extra pounds raises the risk of ills such as heart disease and diabetes and therefore the risk of a premature death. But does that heightened risk of early death apply across the board to those who are merely overweight? A new analysis of nearly 3 million people suggests maybe not. The finding, published on-line Tuesday in the Journal of the American Medical Assn., pooled data from 97 studies encompassing adult men and women in the United States, Canada, Europe, Australia, China, Taiwan, Japan, Brazil, India and Mexico. A total of 270,000 people died of any cause during the studies. When the scientists crunched the numbers, they found, as expected, that people who were significantly obese — with a body mass index, or BMI, of 35 or more — had shorter life spans on average than those who were of normal weight, defined as having a BMI of 18.5 to 24.9. But the scientists also found that people classified as overweight, with a BMI of 25 to 29.9, died at slightly lower rates — not higher — than those of so-called normal weight. And they found that those who were mildly obese, with a BMI of 30 to 34.9, died in no greater numbers than did their normal-weight peers".

Is it not a disservice to humanity when scientists supposed to be searching for truth in whatever they do, indulge in such semantics putting the consumers in great distress not knowing what to believe? A closer scrutiny of the new findings reveals that the conclusions are based on crunching of health  data of thousands of persons and their past history. Though the data have been statistically analyzed, it is difficult to fully comprehend the significance of the new conclusion because a wrong reading can lead to millions of people presently on diet control, to be less vigilant and disciplined in eating that can have unknown consequences in future. A possible and rational explanation for the above unusual findings can be that those who are overweight might have been suffering from diseases like diabetes, CVD and hypertension, forcing them to resort to good and regular medication making their lives much more protective compared to normal healthy persons.  

V.H.POTTY
http://vhpotty.blogspot.com/
http://foodtechupdates.blogspot.com