Still Life: Excess

Is the U.S. Maxing Out on Obesity and Overweight?

New stats on overweight, obesity, and severe obesity are out from the CDC. We already knew the topline numbers for obesity. On that score, the U.S. reached a record high of 42.3 percent in 2018. But this new release paints a more complete picture. Overall, it suggests we might maxing out on the combined prevalence of obesity and overweight.

The population appears to be shifting from mild overweight to obesity and from milder to more severe obesity. But it looks like the remaining population with a BMI less than 25 may be resistant to gaining weight. The prevalence of BMI > 25 does not appear to be growing as fast as it once was.

Resistance to Gaining Weight

From research into the genetic basis of obesity, we know that some portion of the population is indeed resistant to gaining weight. Just like obesity, thinness is a highly heritable trait. Last year, Sadaf Farooqi explained her research on this question:

This research shows for the first time that healthy thin people are generally thin because they have a lower burden of genes that increase a person’s chances of being overweight and not because they are morally superior, as some people like to suggest.

Age-adjusted trends in overweight, obesity, and severe obesity

Obesity Grows More Severe

The new data from CDC tell us that the prevalence of mild overweight (BMI 25-30) is actually going down for men. For women, it has been steady for some time, in the range of 25 to 30 percent of all women 20 years and older. By comparison, the number for men, though it is dropping, remains above 30 percent.

But that’s not exactly good news, because the prevalence of obesity and severe obesity is continuing to grow for both men and women. Severe obesity prevalence has more than doubled in less than 20 years. It affects ten percent of all adults. People who are heavy seem to be getting heavier, while those who have remained thin are tending not to budge.

The bottom line here is relatively simple. A portion of the population is resistant to the forces in our environment that are triggering more obesity. It looks like that number might be between 20 and 25 percent of all adults. For the rest of us, obesity is growing more prevalent and more severe.

Click here for the report from CDC and here for further perspective.

Still Life: Excess. Painting by Albert Anker / WikiArt

Subscribe by email to follow the accumulating evidence and observations that shape our view of health, obesity, and policy.


 

December 14, 2020