There are several standards for categorizing the percentage of body weight that
is made up of fat with regard to healthy weights. The National Heart, Lung, and
Blood Institute’s weight categories are underweight (BMI of <18.5), normal weight
(BMI of 18.5–24.9), overweight (BMI of 25–29.9), obesity (BMI of ≥30) and extreme
morbid obesity a BMI of 40 or greater. The World Health Organization uses
a different standard, with an obesity cut-off of equal or greater than BMI ≥25 for
men and BMI ≥35 for women.
Although widely used in research and for patient counseling, the BMI is not a direct
measure of fat and is subject to under-diagnosis of obesity. For example, Shah
and Braverman compared BMIs to body fat percentage determined by dual-energy
x-ray absorptiometry (DEXA). They found that 39% (22% of men and 48% of
women) were not classified as obese according to their BMI, but their fat percentage
showed that they were, (the study defined obesity as a BMI of greater than 25 for
men and greater than 30 for women).
The loss of muscle mass in older women caused the greatest disparity in classification.
In contrast, 25% of muscular men were misclassified as being obese when
they were not. The investigators suggest that the diagnosis of obesity based on BMI
could be made more accurate by lowering the cut-off threshold for obesity from a
BMI of 30 to 28 for men and from a BMI of 30 to 24 for women. According to the
revised standard, 64% of American women are obese.
This blog presents opinions and ideas and is intended to provide helpful general information. I am not engaged in rendering advice or services to the individual reader. The ideas, procedures and suggestions in that are presented are not in any way a substitute for the advice and care of the reader’s own physician or other medical professional based on the reader’s own individual conditions, symptoms or concerns. If the reader needs personal medical, health, dietary, exercise or other assistance or advice the reader should consult a physician and/or other qualified health professionals. The author specifically disclaims all responsibility for any injury, damage or loss that the reader may incur as a direct or indirect consequence of following any directions or suggestions given in this blog or participating in any programs described in this blog or in the book, The Building Blocks of Health––How to Optimize Your Health with a Lifestyle Checklist (available in print or downloaded at Amazon, Apple, Barnes and Noble and elsewhere). Copyright 2021 by J. Joseph Speidel.