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Stuck Under the Food Pyramid

The scientists who dared to question the diet-heart hypothesis were ignored, silenced, or canceled.

A survey from spring of 2021 found that the 42 percent of American adults who reported gaining weight during the pandemic put on an average of 29 pounds. Another 10 percent of those surveyed reported a gain of more than 50 pounds. Meanwhile, a study by Griffith University found that “[h]ypertension was the most common comorbidity in COVID-19 patients, followed by obesity and diabetes.” Barricaded inside to avoid Covid-19, Americans were making themselves even more vulnerable to the disease. It’s akin to 1940 Londoners turning on the neon signs just before they rushed inside to dodge the blitz. 

But getting fatter is not something new; we have been at it the last few decades, turning ourselves into a collection of comorbidities. Only 10 percent of Americans were obese in the 1950s. Today, that rate is 42 percent. The extreme-obesity rate has doubled in the last 20 years to 9.2 percent, nearly equal the total obesity rate in the ’50s. Something has gone spectacularly wrong and we seem barely to have noticed it. 

You might see headlines or television reports about the obesity epidemic, but what is seldom if ever discussed is why obesity has quadrupled in the last few decades. Did Americans of all economic levels have better choices in the ’50s than now? Did the supposed “food desert” problem get worse? 

When Nina Teicholz wrote her book The Big Fat Surprise: Why Butter, Meat and Cheese Belong in a Healthy Diet back in 2014, she challenged 40 years of conventional wisdom on dieting. “Almost nothing that we commonly believe today about fats generally and saturated fat in particular appears, upon close examination, to be accurate,” she wrote in the introduction. “[F]or many years the public has been presented with the appearance of a uniform scientific consensus on the subject of fat, especially saturated fat, but this outward unanimity was only made possible because opposing views were pushed aside.” 

The man behind that scientific consensus was Ancel Keyes, the American physiologist principally responsible for the diet-heart hypothesis—the idea that cholesterol and saturated fat cause heart disease. He had directed an epidemiological study based on seven countries that purported to back his conclusions. Keyes’s work came at a pivotal moment, just as heart disease had become a major concern in the late 1950s. His ideas spread to central players, such as the American Heart Association (AHA), which had grown from being an obscure outfit to become a major source of influence on heart-health issues. Procter & Gamble, a major purveyor of vegetable oil, gave the AHA $1.5 million in 1948. 

As is always the case, whatever becomes dominant in culture or science eventually finds its way into politics. In 1977, a Senate committee published a report titled Dietary Goals, recommending that Americans “eat more fruits, vegetables, and whole grains, and less high-fat meat, egg, and dairy products.” The Dietary Goals report is the predecessor of what later became known as the food pyramid, a visual representation of what constitutes a good diet. At the base of that pyramid, signifying what foods should be eaten most, are bread, cereal, rice, and pasta. Then, a smaller space in the pyramid is occupied by fruits and vegetables. An even smaller space is reserved for milk, yogurt, cheese, meat, poultry, fish, dry beans, eggs, and nuts. At the top of the pyramid, the smallest space of all, is for fats, oils, and sweets. 

As Teicholz documented in her book, Americans over time have adjusted their dietary habits to more closely reflect official dietary recommendations: “Since the 1970s, we have successfully increased our fruits and vegetables by 17 percent, our grains by 29 percent, and reduced the amount of fat we eat from 43 percent to 33 percent of calories or less.” Our consumption of beef has declined at least by a third since the ‘70s, while our consumption of chicken has doubled. Meanwhile, there has been a meteoric rise (between 200 and 400 percent) in the consumption of cooking oils, corn sweeteners, corn products, and rice in that same time. Consumption of saturated fat, which is the fat found in animal foods like pork and beef, eggs, and full-fat dairy products, has been going down, while the consumption of carbohydrates has been steadily increasing, especially since the ’70s.

In the past, Americans did not eat a diet high in carbohydrates. Their diet was high in saturated fats. Heart disease was rare, and obesity was limited to a small percentage of the population. This is not unique to pre-1970s America. Populations around the world that consumed high-saturated-fat diets have exhibited similar results. For example, Teicholz mentions the work of George V. Mann, a doctor and professor of biochemistry, who visited the Maasai people in Africa in the 1960s with a research team from Vanderbilt University. Mann had heard that “the [Maasai] men ate nothing but meat, blood, and milk—a diet, like the Inuits’, comprised of almost entirely animal fat—and that they considered fruits and vegetables fit to be eaten only by cows.” Maasai men had blood pressure and weight “50 percent lower than their American counterparts—and, most significantly, these numbers did not rise with age.” Moreover, it was observed that when Masai men moved to urban centers and adopted a modern diet, they were also struck with obesity, diabetes, heart disease, and a much higher occurrence of cancer. 

The diet-heart hypothesis has gradually become the official dogma of all major diet and health-related institutions since the ’60s. Its dominant position was further solidified when food-industry conglomerates realized their interests aligned almost perfectly with the dietary implications of the hypothesis. It is dumbfounding, however, to see how thin the scientific evidence for the diet-heart hypothesis is. 

The scientists who dared to question the hypothesis—and they were not few—were ignored, silenced, or canceled. In 1980, a skeptical president of the National Academy of Sciences, Philip Handler, spoke of a “vast nutritional experiment.” Decades later we are living with the consequences of that “experiment.” Even today, with millions of lives destroyed and impaired, we have not started talking about why we ditched traditional diets for a feebly supported set of theories and industrial food products. 

The history of the diet-heart hypothesis fits in with a familiar pattern. An idea offers a plausible explanation for and solution to an issue of public concern. The propagators of said idea execute a long march through the institutions. After they have gained control, all opposition is deemed heretical, controversial, and dangerous. The science is settled, and to question those in power is to question science itself. Any subsequent evidence of the idea’s failure only serves the narrative that those in power deserve even more power to deal with the even greater problem at hand.

Napoleon Linarthatos is a writer based in New York.