I’m sure a lot of you read about the rather startling results published last September of a very big study comparing the long-term health effects of low-fat and low-carbohydrate diets. Not only did the low-carb cohort lose a lot more weight, and the kind of weight you want to lose; but they actually lowered their risk of heart disease despite a significantly higher consumption of saturated fats, generally thought to be the heart-healthy boogeyman.

While this looked to be new evidence that defied the existing scientific consensus, it actually confirmed long-standing evidence that had been more or less politically repressed. That’s the conclusion reached by former NPR reporter Nine Teicholz in a new book entitled The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet. It is reviewed in the new issue of the Washington Monthly by WaMo books editor Kukula Glastris.

As Glastris explains, the idea that saturated fats caused heart disease and should be sharply reduced as a component of diets went back to a sustained campaign from the American Heart Association and the U.S. Department of Agriculture backed by vegetable oil and processed foods industries. But it never reflected a true scientific consensus, and depended on a series of political strokes of luck for the anti-animal-fat lobby, including the relationship of the nation’s top advocate for low-fat diets with President Eisenhower’s physician, and much later, the hostility of a key Democratic Senate staffer to the cattle and dairy lobbies. It took the discovery and study of the dangerous effects of “trans-fats” to turn the zeitgeist around.

Here’s how Glastris sums up the lesson of this story:

Some of the media coverage that has greeted The Big Fat Surprise has described the book as an indictment of science. But that is not really the story Teicholz tells. Rather, as her book shows, time and again a consensus of scientists called it right, insisting that the weight of the evidence was insufficient to support the anti-saturated-fat position. What really happened is that, over the course of several decades, a relatively small network of zealous, well-connected, enterprising scientists, working with well-funded industry partners, managed to take control of key scientific institutions inside and outside of government. That gave them the power to roll the scientific consensus. The media and political leaders who went along were, for the most part, too ignorant of the underlying power dynamics to understand that they were being played. And that, unfortunately, is pretty typical of how Washington works to this day.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.