Good Calories, Bad Calories

placebo, and then followed for at least five years. Heart disease, breast cancer, stroke, and dementia were all more common in the women prescribed hormone replacement than in those on placebos.^*11

The episode was an unfortunate lesson in what the epidemiologist David Sackett memorably called the “disastrous inadequacy of lesser evidence.” In an editorial published in August 2002, Sackett argued that the blame lay solely with those medical authorities who, for numerous reasons, including “a misguided attempt to do good, advocate ‘preventive’ maneuvers that have never been validated in rigorous randomized trials. Not only do they abuse their positions by advocating unproven ‘preventives,’ they also stifle dissent.”

From 1960 onward, those involved in the diet-heart controversy had intended to conduct precisely the kind of study that three decades later would reverse the common wisdom about the long-term benefits of hormone- replacement therapy. This was the enormous National Diet-Heart Study that Jeremiah Stamler in 1961 had predicted would take five or ten years of hard work to complete. In August 1962, the National Heart Institute awarded research grants to six investigators—including Stamler, Keys, and Ivan Frantz, Jr.—to explore the feasibility of inducing a hundred thousand Americans to change the fat content of their diet.^*12 In 1968, the National Institutes of Health assembled a committee led by Pete Ahrens of Rockefeller University to review the evidence for and against the diet-heart hypothesis and recommend how to proceed. The committee published its conclusions in June 1969. Even though the American Heart Association had been recommending low- fat diets for almost a decade already, Ahrens and his colleagues reported, the salient points remained at issue. “The essential reason for conducting a study,” they noted, “is because it is not known whether dietary manipulation has any effect whatsoever on coronary heart disease.” And so they recommended that the government proceed with the trial, even though, Ahrens recalled, the committee members came to believe that any trial large enough and sufficiently well controlled to provide a reliable conclusion “would be so expensive and so impractical that it would never get done.”

Two years later, the NIH assembled a Task Force on Arteriosclerosis, and it came to similar conclusions in its four-hundred-page, two-volume report. The task force agreed that a “definitive test” of Keys’s dietary-fat hypothesis “in the general population is urgently needed.” But these assembled experts also did not believe such a study was practical. They worried about the “formidable” costs—perhaps $1 billion—and recommended instead that the NIH proceed with smaller, well-controlled studies that might demonstrate that it was possible to lessen the risk of coronary heart disease without necessarily relying on diet to do it.

As a result, the NIH agreed to spend only $250 million on two smaller trials that would still constitute the largest, most ambitious clinical trials ever attempted. One would test the hypothesis that heart attacks could be prevented by the use of cholesterol-lowering drugs. The other would attempt to prevent heart disease with a combination of cholesterol-lowering diets, smoking-cessation programs, and drugs to reduce blood pressure. Neither of these trials would actually constitute a test of Keys’s hypothesis or of the benefits of low-fat diets. Moreover, the two trials would take a decade to complete, which was longer than the public, the press, or the government was willing to wait.

Chapter Three

CREATION OF CONSENSUS

In sciences that are based on supposition and opinion…the object is to command assent, not to master the thing itself.

FRANCIS BACON, Novum Organum, 1620

BY 1977, WHEN THE NOTION THAT dietary fat causes heart disease began its transformation from speculative hypothesis to nutritional dogma, no compelling new scientific evidence had been published. What had changed was the public attitude toward the subject. Belief in saturated fat and cholesterol as killers achieved a kind of critical mass when an anti-fat, anti-meat movement evolved independent of the science.

The roots of this movement can be found in the counterculture of the 1960s, and its moral shift away from the excessive consumption represented by fat-laden foods. The subject of famine in the third world was a constant presence in the news: in China and the Congo in 1960, then Kenya, Brazil, and West Africa—where “Villagers in Dahomey Crawl to Town to Seek Food,” as a New York Times headline read—followed by Somalia, Nepal, South Korea, Java, and India; in 1968, Tanzania, Bechuanaland, and Biafra; then Bangladesh, Ethiopia, and much of sub-Saharan Africa in the early 1970s. Within a decade, the Stanford University biologist Paul Ehrlich predicted in his 1968 best-seller, The Population Bomb, “hundreds of millions of people are going to starve to death in spite of any crash programs embarked upon now.”

The fundamental problem was an ever-increasing world population, but secondary blame fell to an imbalance between food production and consumption. This, in turn, implicated the eating habits in the richer nations, particularly the United States. The “enormous appetite for animal products has forced the conversion (at a very poor rate) of more and more grain, soybean and even fish meal into feed for cattle, hogs and poultry, thus decreasing the amounts of food directly available for direct consumption by the poor,” explained Harvard nutritionist Jean Mayer in 1974. To improve the world situation, insisted Mayer and others, there should be “a shift in consumption in developed countries toward a ‘simplified’ diet containing less animal products and, in particular, less meat.” By doing so, we would free up grain, the “world’s most essential commodity,” to feed the hungry.

This argument was made most memorably in the 1971 best-seller Diet for a Small Planet, written by a twenty-six-year-old vegetarian named Francis Moore Lappe. The American livestock industry required twenty million tons of soy and vegetable protein to produce two million tons of beef, according to Lappe. The eighteen million tons lost in the process were enough to provide twelve urgently needed grams of protein daily to everyone in the world. This argument transformed meat-eating into a social issue, as well as a moral one. “A shopper’s decision at the meat counter in Gary, Indiana would affect food availability in Bombay, India,” explained the sociologist Warren Belasco in Appetite for Change, his history of the era.

By the early 1970s, this argument had become intertwined with the medical issues of fat and cholesterol in the diet. “How do you get people to understand that millions of Americans have adopted diets that will make them at best fat, or at worst, dead?” as the activist Jennifer Cross wrote in The Nation in 1974. “That the $139 billion food industry has not only encouraged such unwise eating habits in the interest of profit but is so wasteful in many of its operations that we are inadvertently depriving hungry nations of food?” The American Heart Association had taken to recommending that Americans cut back not just on saturated fat but on meat to do so. Saturated fat may have been perceived as the problem, but saturated fat was still considered to be synonymous with animal fat, and much of the fat in the American diet came from animal foods, particularly red meat.

Ironically, by 1968, when Paul Ehrlich had declared in The Population Bomb that “the battle to feed all humanity” had already been lost, agricultural researchers led by Norman Borlaug had created high-yield varieties of dwarf wheat that ended the famines in India and Pakistan and averted the predicted mass starvations. In 1970, when the Nobel Foundation awarded its Peace Prize to Borlaug, it justified the decision on the grounds that, “more than any other single person,” Borlaug had “helped to provide bread for a hungry world.”