Unlike the reaction to Cleave’s hypothesis, which garnered little attention even after Cleave testified to McGovern’s Select Committee, the media pounced on the fiber hypothesis almost immediately. After Trowell published a pair of articles on fiber and heart disease in The American Journal of Clinical Nutrition in 1972, Robert Rodale, a nationally syndicated columnist, wrote a series of articles on the research, touting fiber as the answer to heart disease and obesity. Rodale was president of Rodale Press and the Rodale Institute, both dedicated to furthering the cause of organic foods and chemical-and pesticide-free “regenerative” agriculture. Rodale saw Burkitt and Trowell’s fiber hypothesis as validation of the wisdom of organic foods and the agrarian lifestyle. “The natural fiber in whole processed foods may be instrumental in keeping cholesterol levels low and preventing the onset of heart disease,” he wrote.

Burkitt and Alec Walker followed up Trowell’s articles with an August 1974 review in The Journal of the American Medical Association discussing the causal chain from fiber to constipation and “changes in gastrointestinal behavior” to the entire spectrum of Western diseases. The Washington Post wrote up the JAMA article on the day of its release, calling fiber “the tonic for our time.” That December, Reader’s Digest published an article on Burkitt and the fiber hypothesis; a year later, the magazine claimed that sales of fiber-rich products had more than doubled since the article. The breakfast-cereal industry, led by Kellogg and General Foods, immediately started pushing bran and fiber as inherent heart-healthy aspects of their products. In 1975, Burkitt and Trowell published a book, Refined Carbohydrate Foods and Disease.

Burkitt then spent the next decade lecturing on the dangers of fiber-poor diets. He would condemn modern diets equally for their “catastrophic drop in starch,” for their high fat content—“We eat three times more fat than communities with a minimum prevalence of [Western] diseases,” he would say; “We must reduce our fat!”—and for their lack of fiber, which he considered “the biggest nutritional catastrophe in [the United Kingdom] in the past 100 years.”

Not everyone bought into it. For public-health authorities and health reporters, dietary fat and/or cholesterol continued to be the prime suspects in chronic disease, and dietary fat had already been linked through international comparisons to colon cancer, as well as breast cancer. Burkitt recalled memorable disputes with researchers in the United States who blamed colon cancer on dietary fat, but he insisted that the absence of fiber was responsible. Eventually, they compromised. His opponents, said Burkitt, conceded “that the fact that fat happened to be causative…did not preclude the possibility that fiber might be protective.” Harvard nutritionist Jean Mayer also discounted the significance of fiber, after Burkitt, Walker, and Trowell’s early papers sparked the “furor over fiber” in the United States. But then Mayer, too, saw the wisdom of compromise. The ideal diet, he noted, would minimize the risk of both heart disease and cancer. It would be low in fat, or at least low in saturated fat, and so would be low in meat and dairy products. And it would be high in fiber. “A good diet,” Mayer wrote, “high in fruits and vegetables and with a reasonable amount of undermilled cereals—will give all you need of useful fiber.” The assumption that it would lead to long life and good health, however, was based more on faith and intuition than on science.