The New York Times reports on an OECD article showing that 28% of the US population is obese, and 68% is overweight. (more on the OECD here)
I can’t find anywhere in the article or in the main page for the report itself how they measured obesity and overweight.
If they used BMI (body-mass index, the proportion of a person’s height to their weight), these numbers are highly questionable. While the trend may be the same (upward), the total percentages could be significantly lower.
BMI figures do not account for muscle-mass. According to BMI charts, I, at 6 feet tall, 200 pounds, am “overweight,” and verge on “obese.”
If you’ve seen me, you might differ.
There is an argument that BMI is accurate because different heights have different “ideal weights,” but this argument has been debunked several times in several places.
First, it does not account for normal variation in the species (some people are shorter, but have “stocky” frames that can carry more muscle) – a flaw in statistical analyses generally (pun intended). Secondly, it does not account for the most important quality of living organisms – adaptation.
As we’ve seen in Tibetan populations, genetic adaptation can occur in as little as 5000 years. Structural adaptation occurs much more quickly, as anyone who has embarked on a serious exercise regimen can attest.
The body changes to meet the demands placed upon it.
Carol Torgan reports on the most recent Health Affairs issue in her blog, summing up the articles in that journal relating to childhood obesity statistics.
Again, all of the studies I saw in that journal use BMI as the measuring stick. This is discouraging, when we know that BMI is an unreliable measure for body fatness.
But what I like about Carol’s summary is that it shows all of the factors that contribute to obesity. To really “address” or “solve” the obesity “problem,” you have to address all of those issues, and one more fundamental underlying issue – the culture that supports the creation of those issues.