I found BMI charts to be misleading when it comes to assessing an individuals weight and giving a healthy weight range.
I have kept a spreadsheet of my fitness goals and weight and body fat percentage that I make an entry into weekly. My thought process is if I am always tracking it then how can I left myself slowly slip back into being out of shape. One column I had in my spreadsheet I entered my BMI but as I reached my "goals" I realized that being in the "normal" range of under 25 was not really the normal healthy goal for me. Once I got under 192 I was no longer considered obese (I had felt comfortable in my own skin at about 205) I am currently in the overweight range for my height. I think to be in normal range I need to be under 160-165. When I was eating strictly on a healthy diet and working out 6 days a week I managed to get down to 173 but I have a large rib cage that stuck out. Since then I added muscle mass and stayed between 179-184.
I am not a fan of BMI which is what the healthy industry uses in statistics and recommending ideal weight. It was designed to measure an entire population and not individuals. Waist to hip ratio and body fat percentage are better tools to determine at risk people.
Here is 10 Reasons Why The BMI Is Bogus
1. The person who dreamed up the BMI said explicitly that it could not and should not be used to indicate the level of fatness in an individual.
The BMI was introduced in the early 19th century by a Belgian named Lambert Adolphe Jacques Quetelet. He was a mathematician, not a physician. He produced the formula to give a quick and easy way to measure the degree of obesity of the general population to assist the government in allocating resources. In other words, it is a 200-year-old hack.
2. It is scientifically nonsensical.
There is no physiological reason to square a person's height (Quetelet had to square the height to get a formula that matched the overall data. If you can't fix the data, rig the formula!). Moreover, it ignores waist size, which is a clear indicator of obesity level.
3. It is physiologically wrong.
It makes no allowance for the relative proportions of bone, muscle and fat in the body. But bone is denser than muscle and twice as dense as fat, so a person with strong bones, good muscle tone and low fat will have a high BMI. Thus, athletes and fit, health-conscious people who work out a lot tend to find themselves classified as overweight or even obese.
4. It gets the logic wrong.
The CDC says on its Web site that "the BMI is a reliable indicator of body fatness for people." This is a fundamental error of logic. For example, if I tell you my birthday present is a bicycle, you can conclude that my present has wheels. That's correct logic. But it does not work the other way round. If I tell you my birthday present has wheels, you cannot conclude I got a bicycle. I could have received a car. Because of how Quetelet came up with it, if a person is fat or obese, he or she will have a high BMI. But as with my birthday present, it doesn't work the other way round. A high BMI does not mean an individual is even overweight, let alone obese. It could mean the person is fit and healthy, with very little fat.
5. It's bad statistics.
Because the majority of people today (and in Quetelet's time) lead fairly sedentary lives and are not particularly active, the formula tacitly assumes low muscle mass and high relative fat content. It applies moderately well when applied to such people because it was formulated by focusing on them. But it gives exactly the wrong answer for a large and significant section of the population, namely the lean, fit and healthy. Quetelet is also the person who came up with the idea of "the average man." That's a useful concept, but if you try to apply it to any one person, you come up with the absurdity of a person with 2.4 children. Averages measure entire populations and often don't apply to individuals.
6. It is lying by scientific authority.
Because the BMI is a single number between 1 and 100 (like a percentage) that comes from a mathematical formula, it carries an air of scientific authority. But it is mathematical snake oil.
7. It suggests there are distinct categories of underweight, ideal, overweight and obese, with sharp boundaries that hinge on a decimal place.
That's total nonsense.
8. It makes the more cynical members of society suspect that the medical insurance industry lobbies for the continued use of the BMI to keep their profits high.
Insurance companies sometimes charge higher premiums for people with a high BMI. Among such people are all those fit individuals with good bone and muscle and little fat, who will live long, healthy lives during which they will have to pay those greater premiums.
9. Continued reliance on the BMI means doctors don't feel the need to use one of the more scientifically sound methods that are available to measure obesity levels.
Those alternatives cost a little bit more, but they give far more reliable results.
10. It embarrasses the U.S.
It is embarrassing for one of the most scientifically, technologically and medicinally advanced nations in the world to base advice on how to prevent one of the leading causes of poor health and premature death (obesity) on a 200-year-old numerical hack developed by a mathematician who was not even an expert in what little was known about the human body back then.
Category BMI ranges:
Severely underweight less than 16.5
Underweight from 16.5 to 18.4
Normal from 18.5 to 24.9
Overweight from 25 to 29.9
Obese Class I from 30 to 34.9
Obese Class II from 35 to 39.9
Obese Class III over 40
I guess if I really cared about BMI I could shed some muscle mass and get thin to conform with what the CDC and health industry considers normal/healthy. A formula that only considers height and weight should not be valid
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