Obesity Science Has a Leadership Problem
What happens to a scientific discipline when questioning assumptions isn't on the agenda and second rate science is accepted as good enough?
What is a golden age like, in a science? … the obvious first requirement is that the science be just a-borning, nascent, small. Certainly that small size at the start of a new field is crucial.…The small size maximizes the collision frequency, the intensity of intellectual interactions; the variety of starting points maximizes the interplay, the scope and angle of intersection of ideas… both concepts and experiments can have a freshness and simplicity that, among much else, may mean that the actual costs of research are low, in absolute terms but especially in relation to the payout. And that payout! Great principles, often radically simplifying theories clearing away overgrown, encrusted complexities.
Horace Freeland Judson, The Eighth Day of Creation: Makers of the Revolution in Biology
The science of obesity never had a golden age. Obesity therapy might be having one now, depending on how you think about the long-term promise of the GLP-1 drugs, but the science… not so much.
A century and a quarter into serious thinking on the subject, and the unquestioned conventional wisdom remains the simplistic concept that it was in 1900: people get fat because they eat too much—albeit now considered a disorder of the brain, a dysregulation of eating behavior—despite the fact, also clear in 1900, that the world is full of people who get excessively fat eating no more food than the lean do.
We still have a discipline in which the most influential nutritionist since the 1990s can refer to the most influential obesity-related paper of the last decade as “worse than worthless,” and the author of that paper can continue to promote its results as though they’re not controversial and have never been criticized (and to do so in The New York Times no less).
To understand this situation, we need to examine what makes science self-correcting—and what obesity research has (mostly) lacked for the last eighty years, at least.
When I first started my research on obesity back in the early 2000s, I could still find a few leaders in the field who were willing to accept that they had made little or no progress over the course of their long careers. The implications of how they thought about obesity—the fat-people-eating-too-much assumption—had explained precious little that they wanted to know.
Jules Hirsch of Rockefeller University, for instance, whom The Washington Post once described as having “helped reframe the modern understanding of obesity,” told me in 2002, shortly before he retired, that he considered his career an abject failure. After almost 40 years of work, he said, he could no more explain how people get fat to begin with than he could explain how they can lose weight and keep it off once they do.
Sure eating too much was the problem, Hirsch believed, but when he and his colleagues overfed lean people in their experiments, the lean people got fatter, as expected, but they then promptly returned to their original leanness when the experiment ended. That was a ubiquitous observation in the field. The same was true for animals. So what made the lean people in Hirsch’s experiments different from the people in the real world who get fat and stay fat? This was a mystery to Hirsch. “I’ve been working on this for a hell of a long time,” Hirsch told me. “You’d think I would have gotten a little further along with it.”
For much of his career, Hirsch had worked with the Columbia University researcher Rudy Leibel on experiments that were considered to be seminal. The ones that had helped reframe modern understanding of obesity. It was Leibel who told me that if I do ever feel I “understand this” – “this” being why people ultimately get fat – “it will probably indicate that you’ve lost your mind.”
I can’t say that’s not a reasonable bet (with apologies for the double negative), but there’s another way to see it.
One of the facts that amazed me about researchers like Leibel and Hirsch, bright and self-reflective as they clearly were, is that they never made a concerted effort to find out what they might have missed. They faced what seemed to be an unresolvable paradox. Yet they never asked whether another theoretical framework—something other than this overeating conception—might have provided a way to untangle it.
This seemed to be the kind of investigation scientists would naturally do in a functioning field—step one, in effect, to resolve the conflict between theory and sanity—but in obesity science, no one ever did it. Or rather, they left the job up to a journalist like myself. This suggested a systemic failure of the entire field, which I suggested in the epilogue of Good Calories, Bad Calories. That, in turn, became a natural criticism of my work. Let’s be serious! Who’s more likely to be right about obesity? The journalist or the research community at large (with a few, of course, critical exceptions)?
In 2009, for instance, I lectured on what the field had missed (right or wrong) to a packed auditorium at the Pennington Biomedical Research Center in Louisiana, which is the country’s largest academic obesity research center. In the Q&A following my presentation, one of the researchers—mid-sixties then, I’d say, elegant, with a slight European accent—raised his hand and asked me very politely the obvious question: “Is one subtext of your work that you think we’re all idiots?”
My equally polite answer was, “no, of course not.” What I added, though, was that the generations of obesity researchers that had entered the field from the 1950s onward had launched their careers assuming as a given this theoretical framework about obesity—we get fat because we eat too much—that seemed intuitively obvious but answered no meaningful questions and had never been rigorously tested. That didn’t bother them because it didn’t bother their mentors, the generations that had preceded them. They hadn’t explored the implications of their overeating hypothesis—what it says, for instance, about willpower and the inevitability of fat shaming—because the teachers they respected hadn’t thought to do so. They didn’t go looking for alternative theoretical frameworks, because their teachers and mentors didn’t see the need.
Everyone accepted a way of thinking about obesity because it seemed obvious, even as it made little or no sense. One generation bequeathed a culture of science absent the necessary ingredient of critical thinking to the next generation and it has followed from then on down.
Obesity science, in short, has never been self-correcting, as science is supposed to be, because it lacked what’s necessary to make the corrections, beginning with the intellectual leadership that insisted (and, ideally, still does) on a culture of first rate science.1
What (very) good science looks like as a comparison
To understand this, it helps to understand first rate science. So let’s compare obesity science with disciplines that did experience golden ages in the same era, the middle decades of the last century: molecular biology and particle physics.
