Back in the not-too-distant past, we used to figure out how fat we were by stepping on the bathroom scale.
The more obese we got, as a country, the more we looked for ways to find the scale wrong.
It can't just be about pounds, can it? After all, some people are big-boned, some people are short, some tall.
Sure, you're supposed to figure your weight in conjunction with your height and even age, and while the bathroom scale has become a technologically advanced tool that allows you to store several weight figures in its memory, talk nicely to you and possibly wash your dirty dishes, it doesn't take other important factors into consideration.
At some point, the Body Mass Index became the new scientific way to figure out whether you were fat or lean. The formula works like this:
BMI = weight in pounds/(height in inches x height in inches) x 703.
(The 703 is to convert the index from the original metric version of the formula.)
The Center for Disease Control says a BMI of 18.5 to 24.9 is ideal.
Below 18.5 is underweight; 25.0 to 29.9 means you're overweight, and 30.0 and above means you're obese.
A mathematician named Lambert A.J. Quetelet came up with the BMI formula in the early 19th century as a means to measure the degree of obesity in the general population. He specifically said the BMI should never be used to indicate the level of fatness in an individual. Scientists in the U.S. have ignored that admonishment.
If you do use it on an individual basis, you end up with some of the most physically fit people on the planet falling into the "overweight" category -- people like Michael Jordan, Brad Pitt, Arnold Schwarzenegger (at 30 is considered "obese"!) and Tom Cruise are on that list.
These celebrities may weigh more than the average person because they have more dense muscle tissue, which is heavier than "normal" muscle. Also, strong bones are more dense than loose fat, which would add points to the BMI. The formula, meanwhile, assumes low muscle mass and high relative fat content.
So, although it sounds scientific, the formula is flawed and misleading, and for many people, completely inaccurate.
One thing that isn't considered when looking at the BMI is waist size.
Dr. Memmot Oz, who has appeared on the "Oprah" show many times and is set to begin his own TV program in the fall, has talked at length about how important waist size is to overall health.
From the Oprah.com site: "Instead of focusing on the number on the scale, Dr. Oz says to focus on the number around your waist. The ideal waistline for women is 32 and a half inches and 35 inches for a man - a goal that is achievable by everyone, no matter your age."
Even that seems to be a very one-size-fits-all statement. Thirty-two and a half inches for ALL women? And 35 inches for every man?
On one "Oprah" show, Dr. Oz brought a couple of specimens of an organ called the omentum, which plays a key role in making us fat. The organ stores fat all around the stomach, where the body has easy access to it when or if needed. But the fat creates an inflammatory process that can put you at risk for blocked arteries.
Ideally, the omentum should be thin and lacey, not thick and fatty. That should be reflected in a trim waist rather than a "beer belly."
Body fat can be more accurately measured, perhaps, through a couple of other tests besides the BMI. One can use a body fat caliper to grip a fold of skin at certain points on the body and measure its thickness. Then there's the "immersion" technique: This method is based on the idea that lean tissue (muscles and bones, etc.) tends to sink in water, while fat floats. A person is seated in a chair which hangs from a scale. The person on the chair is lowered into a pool of water until completely immersed, and the person's weight (while immersed) is recorded. The fatter you are, the more you tend to float and the lower your immersed weight will be -- muscular people weigh more than fat people while immersed. This method is very accurate, but it requires a lot of equipment.
One thing is for sure: The Body Mass Index isn't particularly useful as a tool for discovering whether you're fit.
You might as well go back to the bathroom scale; find one that will speak gently to you and give you a bit of encouragement when the numbers seem too high.
Or abandon numbers altogether ... a three-digit number has nothing to do, really, with your worth as a person.
Article Source: http://EzineArticles.com/
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