The dietary fat hypothesis that posited that it was animal fat that caused heart attacks made explaining certain other dietary facts very difficult. The orthodoxy that fat caused heart attacks was sacrosanct, like all orthodoxies, and all dietary theories had to be built around it. To refute the orthodoxy was to risk career ruin. It is still that way. Today’s scientist must not question the orthodoxy of climate change or COVID vaccinations.
But by the 1970s, the consequence of vilifying dietary fat was evident. The ‘diseases of civilization’ were evident everywhere, and the cause was well-known; excessive carbohydrates. Diabetes, obesity, cancer, and even heart attacks were common amoung people who ate very little saturated fat. But, the problem was that no one could recommend a diet of meat and fat anymore. So, another explanation had to be found and this is how fiber was seized upon to explain why high carbohydrate diets were making people sick. The problem, it was explained, was that the carbohydrates that were being consumed where the wrong kind; they were highly refined, sugary, and worse, they did not have enough of the indigestible excess of carbohydrate foods.
Gary Taubes elaborates and follows the years of study and conversation in Good Calories, Bad Calories. Taubes recounts the career of Denis Burkitt, a former missionary doctor who claimed it was the indigestible roughage that was the key to a healthy diet. Burkitt had been a missionary to Uganda in the 1940s and traveled around the US late in the 1960s, and he noted that the black Americans suffered from disease that the Ugandans did not. Ugandans were not obese, did not have cancer, and were not diabetic. He knew the issue was dietary and set out to prove, as other doctors had suggested, that it was fiber, or the lack of it, that was making black Americans sick and keeping black Ugandans healthy.
The original fiber hypothesis had been proposed by a British doctor of lesser fame and so Burkitt lent his reputation to the effort to prove the fiber hypothesis. He used his contacts in Africa to survey the health of people who moved to cities and left their traditional diets behind. These people would inevitably begin to suffer negative heath consequences, such as appendicitis. The change was attributed to refined carbohydrates and Burkitt developed various hypothesis around why this occurred, much it built around the idea of constipation. By removing the fiber from grains, the “transit time” of the food in the bowel was slowed, and the food lingering in the bowel created negative outcomes.
Again, as with the dietary fat hypothesis, Burkitt’s ideas about fiber found a receptive audience with the hippy counter-culturists who viewed industrial agriculture with the same gimlet eye as the consumption of meat. Burkitt wrote many books, including one that is still for sale titled Don’t Forget The Fibre In Your Diet but his ideas were never confirmed and they did not explain away obesity in people who did, in fact, have plenty of fiber in their sugary baked goods. Whole meal cupcakes and whole grain breads did not solve the problem of obesity, and after a time, the need for fiber was an accepted but not comprehensive explanation for the negative health consequences that emerged with the eradication of the native diets around the world.