Why BMI is a bad measure of health or risk

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BMI is a scale which looks at weight alone (without considering how much of the weight is muscle).  The reason everyone likes it, is it's a simple easy number to obtain since it ALSO doesn't concern itself with things like age or even GENDER.

The mathematical formula to obtain BMI was invented in the 1800's.  Researching the origin of BMI on the web, I found the following:

Belgian polymath Adolphe Quetelet devised what we now know as the BMI equation in 1832 as a way to define the "normal man." He never intended for the equation (weight equals height squared) to be used to determine body fat — his project was intended to describe the standard proportions of the human build. The equation was largely ignored by the medical community even though insurance companies began using somewhat vague comparisons of height and weight among policyholders beginning in the early twentieth century.

It was revived in the 1990's.  Originally thought to be a quick way for doctors to know whether to look for certain risk factors in patients usually associated with obesity, BMI soon became the easy single number to know if you were evil (i.e. fat) or good (slim).  The public and diet industry ate it up like apple pie and soon, everyone was being "judged" as healthy or unhealthy by BMI.

In January 2005, the CDC came out with new "obesity and death" figures, stating that NO MORE than 110,000 deaths per year could be connected AT ALL with obesity and this link "may be a weak one".

The lead scientist of the CDC, also stated that a critical analysis of their data found that people whose weights fell within the overweight and obese (and even SEVERELY obese) BMI ranges (26-35) tended to live longer than those whose weights fell within the so called "normal BMI" ranges of 18-25.  She theorized that this might tend to suggest that BMI is an INACCURATE measurement of health risk FOR MOST PEOPLE because the suggested "normal" BMI weights are likely UNDERWEIGHT for many people (and underweight people are still at greater risk than significantly overweight people according to most studies).

A back page article, this new and rather interesting information was greatly ignored by those selling diets who still give the OLD CDC figures of 300,000 deaths a year from "obesity" and advocate judging health by BMI range.

People questioned how good it was to base medical judgments of risk on the Met-Life weight charts because of the rigidity of the charts. Well, if you thought the charts were rigid, the BMI makes the charts look open minded.
 

BMI or Body Mass Index is based on weight alone.

Just weight. It makes no distinctions for age. It makes no distinctions for muscle mass or even bone mass (as did the Met Life charts) and it doesn't even distinguish between male and female. This rigid measurement is being aggressively 'sold' to Health Care professionals as 'more convenient' than the weight charts.

It also puts 60 percent of the American people in the category of needing a diet, since anyone with a BMI over 24 is considered 'at risk', weight-wise.

Among those who are "severely obese" and "at high risk" according to BMI numbers, are bodybuilder now turned governor, Arnold Schwarzenegger!  In fact, most Olympic athletes have a BMI in the "overweight" or "obese" range.
 

BMI Accuracy

Perhaps accuracy was not one of the goals of the committee releasing the new standards for obesity including BMI as a suggested measurement of risk, to replace the weight charts for Health Care professionals. These 'standards' advocate dieting for anyone with a BMI over 24.

At least THREE of the members of the committee, had direct links to pharmaceuticals manufacturing diet pills like "Redux". A fourth member, Dr. Pi-Sunyer is the lead scientist for the program advisory committee of Weight Watchers International.

This committee, ended up besting the insurance companies who set the "original" "ideal" weights on formula.  They dropped 15-20 lbs off the "ideal weight" rending most Americans (60 percent or more) overweight. 

Best bet - BMI should go back to being buried as TOO OLD SCIENCE ... Focus on HEALTH and not WEIGHT.