Does It Matter Why the Population Has So Much Obesity?

Ask any parent. They can tell you that “Why?” can be the most wonderful question a child can bring them. It can also be the most annoying. And so it is with the question of why the population has so much obesity. But it just won’t go away, and in fact the question seems to get even more important as the medical treatment of obesity grows by leaps and bounds.

Yes, obesity is becoming quite a bit more treatable. However, those advances in treatment come at a considerable cost. Right now, only the wealthy and well-insured have consistently good access to advanced obesity medicine, surgery, and professional support for overcoming this disease and its complications. Everyone else gets a dose of blame and DIY aphorisms that does real harm more often than good.

Even if access to care improves dramatically – and we believe it will – the maxim of an ounce of prevention remains important. Right now the go-to strategies for obesity prevention are, at best, minimally effective. So, yes, it matters that we really don’t know why so much more of the population has obesity than it did 50 years ago.

It’s About Knowing

Not knowing exactly why we face this problem is not the same thing as knowing nothing. In an essay for Science, John Speakman, Thorkild Sørensen, Kevin Hall, and David Allison tell us:

“Much has been learned over the past 50 years about the regulation of body fat. Examples include the discovery of the hormone leptin, finding thermogenic brown adipose tissue in adult humans, elucidating pathways in the brain that affect hunger and feeding behavior, quantifying adipocyte turnover and the lipids therein, identifying single genes that produce rare but severe obesity, and finding thousands of genetic variants associated with individual differences in body mass index (BMI). Despite this progress, there remain several key questions to be answered to aid the prevention and treatment of obesity.”

We have plenty of conjecture about the causes of obesity, but as Allison is quick to tell us, “knowing is better.”

Many Factors Working Together

Speakman et al explain that “the false dichotomy of genes versus environment (rather than the combined effects of genes and environment)” hinders our understanding of the causes of obesity.

And those causes are many. The food environment is likely important, but the dimensions of that environment are complex and people argue passionately about the dimensions matter most. Exposures to drugs and chemicals can drive body weight higher. Technology and the built environment serve to make us routinely less active. Social and economic factors of stress and distress cause biological changes that favor higher weights.

We find people who are eager to pluck a single factor out of this complex mixture of contributors to say “This is it.” The current preoccupation with ultra-processed food is but one example. We have to move on from mere conjecture toward better knowledge. Speakman et al sum it up quite well:

“Improving our understanding of environmental drivers and how these interact with genetic composition is vital to making future inroads to this serious medical condition.”

Click here for the full essay from Speakman, Sørensen, Hall, and Allison.

Glaskugel, photograph by Dietmar Rabich, licensed under CC BY-SA 4.0

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September 2, 2023