Why aren’t medical breakthroughs in obesity a bigger deal?

Back in the fraught winter of 2020 when covid vaccines were first authorized but not yet widely available, I found myself as a guest on the “Joe Rogan Experience” podcast.

My goal was to promote and discuss my book on the benefits of greater population density, so I didn’t come prepared to debate vaccines or covid. But Joe Rogan wanted to talk about it and asked me why I was planning to get vaccinated despite the side effects and low objective covid risks to a person my age. I told him the side effects didn’t sound so bad and a large reduction in risk was worth it even from a low baseline. That’s when he hit me with an unexpected cross — why didn’t I put more effort into losing weight?

I’m 6 feet tall, and I was 280 pounds at the time, putting me well into the official obesity territory. Losing weight would clearly lower my covid risks. I didn’t have a good snappy on-air answer, but the truth was like any overweight person, I’d thought about this a lot. And the fundamental problem, a point championed by the fat acceptance movement, is that the instruction Rogan had to give me — improve my diet and exercise — fundamentally doesn’t work.

What’s needed is more acknowledgment that there is a path out of this dead end.

There is also a broader recognition among obesity researchers that the causes of obesity are a complex combination of genetic, social and environmental factors that are most effectively addressed on a social level, much as smoking rates were reduced with policy rather than hectoring.

But to deliver on the promise of this progress, we need a society that’s willing to abandon the binary of “diet and exercise” versus “fat acceptance” in favor of promoting and investing in science-based cures and prevention.

Effective obesity treatments exist, and more are coming

The cost, hassle and general anxiety around surgery is certainly part of the explanation. But what’s more frustrating is that additional, less-invasive evidence-based treatments coming to the fore aren’t getting much attention.

The drug, branded as Wegovy, is an obesity-specific reformulation of a compound called semaglutide that was already approved as a diabetes medication. It’s part of a larger family of drugs called glucagon-like (GLP-1) peptide-1 receptor agonists. This class of drugs works by targeting the hormonal system that we know drives sensations of hunger and satiety, making people feel fuller sooner and helping them make prudent choices about food consumption. Several other GLP-1 agonist drugs approved for diabetes use show promise as general anti-obesity medications. Another, Sexanda, was approved by the FDA in 2020.

These drugs are not miracles. Drug-based weight loss programs that also incorporate coaching claim average losses of about 15 percent. Clinical trials show more modest results than that. A 6-foot-tall, 250-pound man who achieved the optimistic 15 percent would still be considered overweight. But even small amounts can make a big difference. The human body is a mix of fat, lean muscle, water and structural tissue like your bones. For people within a healthy weight range, the heavier tend to be heavier on all four factors. But the difference between an obese person and a merely overweight one is overwhelmingly fat, so medications that generate a 15 percent reduction in body mass are creating disproportionately large reductions in body fat percentage and health outcomes.

Why isn’t this a bigger deal?

But for obesity breakthroughs, we don’t see the same large-scale jubilation among health officials or the public, no calls from elected officials for widespread distribution, no efforts to ensure equitable access and, generally speaking, very little interest in the development.

“Obesity is a complex disease with many contributing factors. Neighborhood design, access to healthy, affordable foods and beverages, and access to safe and convenient places for physical activity can all impact obesity. The racial and ethnic disparities in obesity underscore the need to address social determinants of health such as poverty, education and housing to remove barriers to health. This will take action at the policy and systems level to ensure that obesity prevention and management starts early, and that everyone has access to good nutrition and safe places to be physically active. Policymakers and community leaders must work to ensure that their communities, environments and systems support a healthy, active lifestyle for all.”

None of this is wrong, exactly, but it’s inconceivable that a major public health institution would discuss covid in this way without mentioning vaccines or treatments.

The CDC is correct to point to community level policy change as an important long-term prevention lever. But for those already with obesity — a huge share of the public — short-term remedies are useful and important. During bariatric surgery, a doctor makes small laparoscopic incisions in the patient’s abdomen and surgically alters his or her stomach to become significantly smaller. Study of this practice, in fact, helped to inspire the development of obesity drugs.

We need a new debate

Much of the world is positively convinced that it already knows the cure for obesity and no drugs or surgery are required — the overweight simply need to change their diet and exercise habits. At the same time, there is a tremendous stack of evidence that hectoring people about diet and exercise does not in fact generate weight loss. Instead we simply see a proliferation of stress and anxiety in patients that empowers quacks and perhaps justifies bias and stigma.

Righteous pushback against the genuinely useless diet and exercise mantra has created a new politics of “fat acceptance” especially in certain left circles, which treats any discussion of body weight issues as akin to racist or homophobic discourse. Caught between diet and exercise and its enemies, the idea of effective treatments has no constituency.

The problem with diet and exercise is that while it is a useful framework for preventing obesity (especially in terms of establishing children’s habits) essentially nobody successfully loses weight in a sustainable way through this method.

As Harvard University evolutionary biologist Daniel Lieberman explores in his book, “The Story of the Human Body: Evolution, Health, and Disease,” the idea of maintaining a durable calorie deficit when food is objectively abundant goes against millions of years of primate evolution. In pre-modern conditions it was simply normal to go through periods of time when not enough food was around. That might be a single day when the hunt didn’t work out, a lean season when few crops were available or a whole bad year when bad luck with weather simply didn’t deliver the expected harvest. Animals capable of surviving such conditions need powerful instincts to eat a bit more than is strictly necessary when food is abundant. This is a habit that’s served Homo sapiens well for several hundreds of thousands of years, but happens to be dysfunctional under plenty that have existed for three or four generations at most.

Under these conditions, a staggering array of fad diets can and do work temporarily. Whether diet you’re doing: intermittent fasting, Whole30, paleo, low-carb, low-fat, South Beach or whatever else, you are simply crossing off the list a large share of the foods that happen to be around. This generates weight loss but also constant hunger. Meanwhile, the body’s response to starvation kicks in — metabolism slows and cravings for food increase in the hormonal system tries to inspire what it believes to be a Paleolithic hunter-gatherer to try harder to avert starvation.

Physical activity, meanwhile, though undoubtedly healthy as a general proposition is shown time and again to be a bust in terms of weight control. Working out simply does not burn that many calories, and intense exercise makes people hungry.

That would be convenient if true, but the balance of evidence is just overwhelming. While there are certainly healthy people at all weights, high body fat strongly correlates with stroke, heart attack, diabetes and other serious ailments.

There is no magic cure, but there are safe and effective treatments that complement hard work rather than substituting for it. We should be talking about their existence and how to put them within financial reach of more of the people who need them.