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Is BMI an Accurate Gauge of Obesity?
I read an interesting article in the Wall Street Journal today about a study out of the Mayo Clinic published in the European Heart Journal suggesting that even "normal weight" people can be fat which carries health risk.
The study found that people with a normal body mass index (BMI) but with a high body fat percentage were at high risk of heart problems. The researchers commented that their body's behaved like they are obese, but they are not obese based on their BMI.
Here is my problem with this whole issue: BMI is not an effective measurement of body fat. They are NOT the same thing! BMI is a measure simply of height vs weight. Body fat is not taken into account. How can you call someone obese just based on their height vs weight? And why in the world are the BMI ranges the same for men and women? A BMI less than 25 is considered normal. A range of 25-29.9 is overweight and 30 and over is obese.
In my experience working with clients, I have never met a woman who is at a BMI of 24 or 25 who is happy with her weight. They all desire weight loss. However, a man at a BMI of 25 is pretty lean. We need different standards of BMI for woman than men.
Body fat is a completely different measurement. Yes, a person can be in the "normal weight" category of less than 25 BMI yet have a body fat percentage that is too high (especially as a woman). As someone who has performed countless body fat measurements on people, I can tell you that it is quite possible to be overfat and normal weight. If someone does not exercise and has no significant muscle mass, they can appear normal weight yet under those clothes there is little muscle a lot of fat. You cannot tell a person's body fat percentage with the naked eye. Some obesity is obvious, and some people would surprise you if you saw their body fat percentage.
This study once again proves that body fat is the important factor when it comes to risk of disease--not the number on the scale. Thank goodness we don't walk around with how much we weight written on our foreheads. When will it become acceptable standard practice to measure body fat in a doctor's office instead of just in the gym? The medical community also needs to create a consensus of the proper ranges of body fat since there don't seem to be established standards. Throw out the BMI charts and order in the body fat analyzers!