The Washington Post published an article entitled "Nearly Half of America's Overweight People Don't Realize That They Are Overweight," by Christopher Ingraham. The article prompted me to remind myself on what basis do we evaluate our own weight? So I went to the CDC website and found that the definition of obese and overweight are purely based on one's BMI, which is calculated using only height and weight.
The CDC further states:
BMI is a person's weight in kilograms divided by the square of height in meters. BMI does not measure body fat directly, but research has shown that BMI is moderately correlated with more direct measures of body fat obtained from skinfold thickness measurements, bioelectrical impedance, densitometry (underwater weighing), dual energy x-ray absorptiometry (DXA) and other methods 1,2,3. Furthermore, BMI appears to be as strongly correlated with various metabolic and disease outcome as are these more direct measures of body fatness 4,5,6,7,8,9. In general, BMI is an inexpensive and easy-to-perform method of screening for weight category, for example underweight, normal or healthy weight, overweight, and obesity.
In my estimation, and using a little common sense, BMI is a reasonable indicator of the health status of a person but it is by no means a complete evaluation of health. Yet, unfortunately, as I know from personal experience, conclusions are made about a person's health based solely on BMI. As a personal anecdote, I once applied for life insurance. I am 6' 200 lbs. I exercise daily and am fairly muscular. My BMI calculation yielded the following from the CDC website:
Height: 6 feet, 0 inches
Weight: 200 pounds
Your BMI is 27.1, indicating your weight is in the Overweight category for adults of your height.
For your height, a normal weight range would be from 136 to 184 pounds.
People who are overweight or obese are at higher risk for chronic conditions such as high blood pressure, diabetes, and high cholesterol.
Now I'd like to lose a few pounds just to really get that six pack going, but I'm not exactly sure how to get down to 184, let alone 136!.
The point is that the public perception of their collective weight may not be so "normalized." It may just be that people see the same things I am seeing, have little or no medical training to help guide them, and end up concluding that it is too challenging a topic to figure out. Couple that with the obvious goal of the original WP article, that people need to pay more attention to their health status, and you see why this subject becomes unwieldy.
Public perception could be helped if health officials, and reporters covering these subjects, used more complete definitions of health based on height, weight and body mass characteristics, taking into consideration muscle mass and fat deposits as well as metabolic considerations and preexisting ailments such as hypertension and diabetes, to name just two. Doing so would go a long way towards improving people's understanding of this complex entity we call "obesity."