Good Calories, Bad Calories Part 2

In discussions of dietary fat and heart disease, it is often forgotten that the epidemiologic tools used to link heart disease to diet were relatively new and had never been successful y put to use previously in this kind of chal enge. The science of epidemiology evolved to make sense of infectious diseases, not common chronic diseases like heart disease. Though the tools of epidemiology-comparisons of populations with and without the disease-had proved effective in establis.h.i.+ng that a disease such as cholera is caused by the presence of micro-organisms in contaminated water, as the British physician John Snow demonstrated in 1854, it is a much more complicated endeavor to employ those same tools to elucidate the subtler causes of chronic disease. They can certainly contribute to the case against the most conspicuous determinants of noninfectious diseases-that cigarettes cause lung cancer, for example. But lung cancer was an extremely rare disease before cigarettes became widespread, and smokers are thirty times as likely to get it as nonsmokers. When it comes to establis.h.i.+ng that someone who eats copious fat might be twice as likely to be afflicted with heart disease-a very common disorder-as someone who eats little dietary fat, the tools were of untested value.

The investigators attempting these studies were constructing the relevant scientific methodology as they went along. Most were physicians untrained to pursue scientific research. Nonetheless, they decided they could reliably establish the cause of chronic disease by acc.u.mulating diet and disease data in entire populations, and then using statistical a.n.a.lyses to determine cause and effect. Such an approach "seems to furnish information about causes,"

wrote the Johns Hopkins University biologist Raymond Pearl in his introductory statistics textbook in 1940, but it fails, he said, to do so.

"A common feature of epidemiological data is that they are almost certain to be biased, of doubtful quality, or incomplete (and sometimes al three),"

explained the epidemiologist John Bailar in The New England Journal of Medicine in 1980. "Problems do not disappear even if one has flawless data, since the statistical a.s.sociations in almost any nontrivial set of observations are subject to many interpretations. This ambiguity exists because of the difficulty of sorting out causes, effects, concomitant variables, and random fluctuations when the causes are multiple or diffuse, the exposure levels low, irregular, or hard to measure, and the relevant biologic mechanisms poorly understood. Even when the data are general y accepted as accurate, there is much room for individual judgment, and the considered conclusions of the investigators on these matters determine what they wil label 'cause'..."

The only way to establish cause and effect with any reliability is to do "control ed" experiments, or control ed trials, as they're cal ed in medicine. Such trials attempt to avoid al the chaotic complexities of comparing populations, towns, and ethnic groups. Instead, they try to create two identical situations -two groups of subjects, in this case-and then change only one variable to see what happens. They "control" for al the other possible variables that might affect the outcome being studied. Ideal y, such trials wil randomly a.s.sign subjects into an experimental group, which receives the treatment being tested-a drug, for instance, or a special diet-and a group, which receives a placebo or eats their usual meals or some standard fare.

Not even randomization, though, is sufficient to a.s.sure that the only meaningful difference between the experimental group and the control group is the treatment being studied. This is why, in drug trials, placebos are used, to avoid any distortion that might occur when comparing individuals who are taking a pil in the belief that their condition might improve with individuals who are not. Drug trials are also done double-blind, which means neither subjects nor physicians know which pil s are placebos and which are not. Double-blind, placebo-controlled clinical trials are commonly referred to in medicine as the gold standard for research. It's not that they are better than other methods of establis.h.i.+ng truth, but that truth, in most instances, cannot be reliably established without them.

Diet trials are particularly troublesome, because it's impossible to conduct them with placebos or a double-blind. Diets including copious meat, b.u.t.ter, and cream do not look or taste like diets without them. It is also impossible to make a single change in a diet. Saturated fats cannot be eliminated from the diet without decreasing calories as wel . To ensure that calories remain constant, another food has to replace the saturated fats. Should polyunsaturated fats be added, or carbohydrates? A single carbohydrate or mixed carbohydrates? Green leafy vegetables or starches? Whatever the choice, the experimental diet is changed in at least two significant ways. If saturated-fat calories are reduced and carbohydrate calories are increased to compensate, the investigators have no way to know which of the two was responsible for any effect observed. (To state that "saturated fats raise cholesterol," as is the common usage, is meaningful only if we say that saturated fat raises cholesterol compared with the effect of some other nutrient in the diet-polyunsaturated fats, for instance.) Nonetheless, dietary trials of diet and heart disease began appearing in the literature in the mid-1950s. Perhaps a dozen such trials appeared over the next twenty years. The methods used were often primitive. Many had no controls; many neglected to randomize subjects into experimental and control groups.

Only two of these trials actual y studied the effect of a low-fat diet on heart-disease rates-not to be confused with a cholesterol-lowering diet, which replaces saturated with polyunsaturated fats and keeps the total fat content of the diet the same. Only these two trials ever tested the benefits and risks of the kind of low-fat diet that the American Heart a.s.sociation has recommended we eat since 1961, and that the USDA food pyramid recommends when it says to "use fats and oils sparingly." One, published in a Hungarian medical journal in 1963, concluded that cutting fat consumption to only 1.5 ounces a day reduced heart-disease rates. The other, a British study, concluded that it did not. In the British trial, the investigators also restricted daily fat consumption to 1.5 ounces, a third of the fat in the typical British diet. Each day, the men a.s.signed to this experimental diet, al of whom had previously had heart attacks, could eat only half an ounce of b.u.t.ter, three ounces of meat, one egg, and two ounces of cottage cheese, and drink two ounces of skim milk. After three years, average cholesterol levels dropped from 260 to 235, but the recurrence of heart disease in the control and experimental groups was effectively identical. "A low-fat diet has no place in the treatment of myocardial infarction," the authors concluded in 1965 in The Lancet.

In al the other trials, cholesterol levels were lowered by changing the fat content of the diet, rather than the total amount of fat consumed.

Polyunsaturated fats replaced saturated fats, without altering the calorie content. These diet trials had a profound influence on how the diet/heart-disease controversy played out.

The first and most highly publicized was the Anti-Coronary Club Trial, launched in the late 1950s by New York City Health Department Director Norman Jol iffe. The eleven hundred middle-aged members of Jol iffe's Anti-Coronary Club were prescribed what he cal ed the "prudent diet," which included at least one ounce of polyunsaturated vegetable oil every day. The partic.i.p.ants could eat poultry or fish anytime, but were limited to four meals a week containing beef, lamb, or pork. This made Jol iffe's prudent diet a model for future health-conscious Americans. Corn-oil margarines, with a high ratio of polyunsaturated to saturated fat, replaced b.u.t.ter and hydrogenated margarines, which were high in saturated fats. In total, the prudent diet was barely 30 percent fat calories, and the proportion of polyunsaturated to saturated fat was four times greater than that of typical American diets. Overweight Anti-Coronary Club members were prescribed a sixteen-hundred-calorie diet that consisted of less than 20 percent fat. Jol iffe then recruited a control group to use as a comparison.

Jol iffe died in 1961, before the results were in. His col eagues, led by George Christakis, began reporting interim results a year later. "Diet Linked to Cut in Heart Attacks," reported the New York Times in May 1962. "Special Diet Cuts Heart Cases Here," the Times reported two years later. Christakis was so confident of the prudent-diet benefits, reported Newsweek, that he "urged the government to heed the club results and launch an educational and food-labeling campaign to change U.S. diet habits."

The actual data, however, were considerably less encouraging. Christakis and his col eagues reported in February 1966 that the diet protected against heart disease. Anti-Coronary Club members who remained on the prudent diet had only one-third the heart disease of the controls. The longer you stayed on the diet, the more you benefited, it was said. But in November 1966, just nine months later, the Anti-Coronary Club investigators published a second article, revealing that twenty-six members of the club had died during the trial, compared with only six of the men whose diet had not been prudent. Eight members of the club died from heart attacks, but none of the controls. This appeared "somewhat unusual," Christakis and his col eagues acknowledged.

They discussed the improvements in heart-disease risk factors (cholesterol, weight, and blood pressure decreased) and the significant reduction in debilitating il ness "from new coronary heart disease," but omitted further discussion of mortality.

This mortality problem was the bane of Keys's dietary-fat hypothesis, bedeviling every trial that tried to a.s.sess the effects of a low-fat diet on death as wel as disease. In July 1969, Seymour Dayton, a professor of medicine at the University of California, Los Angeles, reported the results of the largest diet-heart trial to that date. Dayton gave half of nearly 850 veterans residing at a local Veterans Administration hospital a diet in which corn, soybean, safflower, and cottonseed oils replaced the saturated fats in b.u.t.ter, milk, ice cream, and cheeses. The other half, the controls, were served a placebo diet in which the fat quant.i.ty and type hadn't been changed. The first group saw their cholesterol drop 13 percent lower than the controls; only sixty-six died from heart disease during the study, compared with ninety-six of the vets on the placebo diet.*8 Thirty-one of the men eating Dayton's experimental cholesterol-lowering diet, however, died of cancer, compared with only seventeen of the controls.

The risk of death was effectively equal on the two diets. "Was it not possible," Dayton asked, "that a diet high in unsaturated fat...might have noxious effects when consumed over a period of many years? Such diets are, after al , rarities among the self-selected diets of human population groups."

Because the cholesterol-lowering diet failed to increase longevity, he added, it could not provide a "final answer concerning dietary prevention of heart disease."

If these trials had demonstrated that people actual y lived longer on cholesterol-lowering diets, there would have been little controversy. But almost four decades later, only one trial, the Helsinki Mental Hospital Study, seemed to demonstrate such a benefit-albeit not from a low-fat diet but from a high-polyunsaturated, low-saturated-fat diet.

The Helsinki Study was a strange and imaginative experiment. The Finnish investigators used two mental hospitals for their trial, dubbed Hospital K (Kel okoski Hospital) and Hospital N (Nikkila Hospital). Between 1959 and 1965, the inmates at Hospital N were fed a special cholesterol-lowering diet, 9 and the inmates of K ate their usual fare; from 1965 to 1971, those in Hospital K ate the special diet and the Hospital N inmates ate the usual fare. The effect of this diet was measured on whoever happened to be in the hospitals during those periods; "in mental hospitals turnover is usual y rather slow," the Finnish investigators noted.

The diet seemed to reduce heart-disease deaths by half. More important to the acceptance of Keys's hypothesis, the men in the hospitals lived a little longer on the cholesterol-lowering diet. (The women did not.) Proponents of Keys's hypothesis wil stil cite the Helsinki Study as among the definitive evidence that manipulating dietary fats prevents heart disease and saves lives. But if the lower death rates in the Helsinki trial were considered compel ing evidence that the diet worked, why weren't the higher death rates in the Anti-Coronary Club Trial considered evidence that it did not?

The Minnesota Coronary Survey was, by far, the largest diet-heart trial carried out in the United States, yet it played no role in the evolution of the dietary-fat hypothesis. Indeed, the results of the study went unpublished for sixteen years, by which time the controversy had been publicly settled. The princ.i.p.al investigator on the trial was Ivan Frantz, Jr., who worked in Keys's department at the University of Minnesota. Frantz retired in 1988 and published the results a year later in a journal cal ed Arteriosclerosis, which is unlikely to be read by anyone outside the field of cardiology.*10 The Minnesota trial began in November 1968 and included more than nine thousand men and women in six state mental hospitals and one nursing home. Half of the patients were served a typical American diet, and half a cholesterol-lowering diet that included egg subst.i.tutes, soft margarine, low-fat beef, and extra vegetables; it was low in saturated fat and dietary cholesterol and high in polyunsaturated fat. Because the patients were not confined to the various mental hospitals for the entire four and a half years of the study, the average subject ate the diet for only a little more than a year. Average cholesterol levels dropped by 15 percent. Men on the diet had a slightly lower rate of heart attacks, but the women had more. Overal , the cholesterol-lowering diet was a.s.sociated with an increased rate of heart disease. Of the patients eating the diet, 269 died during the trial, compared with only 206 of those eating the normal hospital fare. When I asked Frantz in late 2003 why the study went unpublished for sixteen years, he said, "We were just disappointed in the way it came out." Proponents of Keys's hypothesis who considered the Helsinki Mental Hospital Study reason enough to propose a cholesterol-lowering diet for the entire nation, never cited the Minnesota Coronary Survey as a reason to do otherwise.

As I implied earlier, we can only know if a recommended intervention is a success in preventive medicine if it causes more good than harm, and that can be established only with randomized, control ed clinical trials. Moreover, it's not sufficient to establish that the proposed intervention reduces the rate of only one disease-say, heart disease. We also have to establish that it doesn't increase the incidence of other diseases, and that those prescribed the intervention stay healthier and live longer than those who go without it. And because the diseases in question can take years to develop, enormous numbers of people have to be included in the trials and then fol owed for years, or perhaps decades, before reliable conclusions can be drawn.

This point cannot be unduly emphasized. An unfortunate lesson came in the summer of 2002, when physicians learned that the hormone-replacement therapy they had been prescribing to some six mil ion postmenopausal women-either estrogen or a combination of estrogen and progestin-seemed to be doing more harm than good. The paral els to the dietary-fat controversy are worth pondering. Since 1942, when the FDA first approved hormone replacement therapy (HRT) for the treatment of hot flashes and night sweats, reams of observational studies comparing women who took hormone replacements with women who did not (just as dietary-fat studies compared populations that ate high-fat diets with populations that did not) reported that the therapy dramatical y reduced the incidence of heart attacks. It was only in the 1990s that the National Inst.i.tutes of Health launched a Women's Health Initiative that included the first large-scale, double-blind, placebo-control ed trial of hormone-replacement therapy. Sixteen thousand healthy women were randomly a.s.signed to take either hormone replacement or a placebo, and then fol owed for at least five years. Heart disease, breast cancer, stroke, and dementia were al 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 cal ed 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 Inst.i.tute 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 Inst.i.tutes of Health a.s.sembled a committee led by Pete Ahrens of Rockefel er 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 a.s.sociation had been recommending low-fat diets for almost a decade already, Ahrens and his col eagues 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 recal ed, the committee members came to believe that any trial large enough and sufficiently wel control ed to provide a reliable conclusion "would be so expensive and so impractical that it would never get done."

Two years later, the NIH a.s.sembled 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 a.s.sembled experts also did not believe such a study was practical. They worried about the "formidable" costs-perhaps $1 bil ion-and recommended instead that the NIH proceed with smal er, wel -control ed 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 mil ion on two smal er trials that would stil const.i.tute 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 actual y const.i.tute 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 wil ing to wait.

Chapter Three.

CREATION OF CONSENSUS.

In sciences that are based on supposition and opinion...the object is to command a.s.sent, 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 compel ing new scientific evidence had been published. What had changed was the public att.i.tude toward the subject. Belief in saturated fat and cholesterol as kil ers achieved a kind of critical ma.s.s 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 s.h.i.+ft 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 "Vil agers in Dahomey Crawl to Town to Seek Food," as a New York Times headline read-fol owed by Somalia, Nepal, South Korea, Java, and India; in 1968, Tanzania, Bechua.n.a.land, 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-sel er, The Population Bomb, "hundreds of mil ions 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 fel 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 appet.i.te 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 s.h.i.+ft 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-sel er Diet for a Small Planet, written by a twenty-six-year-old vegetarian named Francis Moore Lappe. The American livestock industry required twenty mil ion tons of soy and vegetable protein to produce two mil ion tons of beef, according to Lappe. The eighteen mil ion 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 wel 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 Appet.i.te 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 mil ions of Americans have adopted diets that wil make them at best fat, or at worst, dead?" as the activist Jennifer Cross wrote in The Nation in 1974. "That the $139 bil ion 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 a.s.sociation 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 stil considered to be synonymous with animal fat, and much of the fat in the American diet came from animal foods, particularly red meat.

Ironical y, by 1968, when Paul Ehrlich had declared in The Population Bomb that "the battle to feed al 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 ma.s.s starvations. In 1970, when the n.o.bel 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."

Other factors were also pus.h.i.+ng the public toward a belief in the evils of dietary fat and cholesterol that the medical-research community itself stil considered questionable. The American Heart a.s.sociation revised its dietary recommendations every two to three years and, with each revision, made its advice to eat less fat increasingly unconditional. By 1970, this prescription applied not just to those high-risk men who had already had heart attacks or had high cholesterol or smoked, but to everyone, "including infants, children, adolescents, pregnant and lactating women, and older persons." Meanwhile, the press and the public came to view the AHA as the primary source of expert information on the issue.

The AHA had an important al y in the vegetable-oil and margarine manufacturers. As early as 1957, the year Americans first purchased more margarine than b.u.t.ter, Mazola corn oil was being pitched to the public with a "Listen to Your Heart" campaign; the polyunsaturated fats of corn oil would lower cholesterol and so prevent heart attacks, it was said. Corn Products Company, the makers of Mazola, and Standard Brands, producers of Fleischmann's margarine, both initiated programs to educate doctors to the benefits of polyunsaturated fats, with the implicit a.s.sumption that the physicians would pa.s.s the news on to their patients. Corn Products Company col aborated directly with the AHA on releasing a "risk handbook" for physicians, and with Pocket Books to publish the revised version, in 1966, of Jeremiah Stamler's book Your Heart Has Nine Lives. By then, ads for these polyunsaturated oils and margarines needed only to point out that the products were low in saturated fat and low-cholesterol, and this would serve to communicate and reinforce the heart-healthy message.

This al iance between the AHA and the makers of vegetable oils and margarines dissolved in the early 1970s, with reports suggesting that polyunsaturated fats can cause cancer in laboratory animals. This was problematic to Keys's hypothesis, because the studies that had given some indication that cholesterol-lowering was good for the heart-Seymour Dayton's VA Hospital trial and the Helsinki Mental Hospital Study-had done so precisely by replacing saturated fats in the diet with polyunsaturated fats. Public-health authorities concerned with our cholesterol dealt with the problem by advising that we simply eat less fat and less saturated fat, even though only two studies had ever tested the effect of such low-fat diets on heart disease, and they had been contradictory.

It's possible to point to a single day when the controversy was s.h.i.+fted irrevocably in favor of Keys's hypothesis-Friday, January 14, 1977, when Senator George McGovern announced the publication of the first Dietary Goals for the United States. The doc.u.ment was "the first comprehensive statement by any branch of the Federal Government on risk factors in the American diet," said McGovern.

This was the first time that any government inst.i.tution (as opposed to private groups like the AHA) had told Americans they could improve their health by eating less fat. In so doing, Dietary Goals sparked a chain reaction of dietary advice from government agencies and the press that reverberates stil , and the doc.u.ment itself became gospel. It is hard to overstate its impact. Dietary Goals took a grab bag of ambiguous studies and speculation, acknowledged that the claims were scientifical y contentious, and then official y bestowed on one interpretation the aura of established fact. "Premature or not," as Jane Brody of the New York Times wrote in 1981, "the Dietary Goals are beginning to reshape the nutritional philosophy of America, if not yet the eating habits of most Americans."

The doc.u.ment was the product of McGovern's Senate Select Committee on Nutrition and Human Needs, a bipartisan nonlegislative committee that had been formed in 1968 with a mandate to wipe out malnutrition in America. Over the next five years, McGovern and his col eagues-among them, many of the most prominent politicians in the country, including Ted Kennedy, Charles Percy, Bob Dole, and Hubert Humphrey-inst.i.tuted a series of landmark federal food-a.s.sistance programs. Buoyed by their success fighting malnutrition, the committee members turned to the link between diet and chronic disease.

The operative force at work, however, was the committee staff, composed of lawyers and ex-journalists. "We real y were total y naive," said the staff director Marshal Matz, "a bunch of kids, who just thought, Hel , we should say something on this subject before we go out of business."*13 McGovern had attended Nathan Pritikin's four-week diet-and-exercise program at Pritikin's Longevity Research Inst.i.tute in Santa Barbara, California. He said that he lasted only a few days on Pritikin's very low-fat diet, but that Pritikin's philosophy, an extreme version of the AHA's, had profoundly influenced his thinking.

McGovern's staff were virtual y unaware of the existence of any scientific controversy. They knew that the AHA advocated low-fat diets, and that the dairy, meat, and egg industries had been fighting back. Matz and his fel ow staff members described their level of familiarity with the subject as that of interested laymen who read the newspapers. They believed that the relevant nutritional and social issues were simple and obvious. Moreover, they wanted to make a difference, none more so than Nick Mottern, who would draft the Dietary Goals almost single-handedly. A former labor reporter, Mottern was working as a researcher for a consumer-products newsletter in 1974 when he watched a television doc.u.mentary about famine in Africa, decided to do something meaningful with his life, and was hired to fil a vacant writing job on McGovern's committee.

In July 1976, McGovern's committee listened to two days of testimony on "Diet and Kil er Diseases." Mottern then spent three months researching the subject and two months writing. The most compel ing evidence, Mottern believed, was the changing-American-diet story, and this became the underlying foundation of the committee's recommendations: we should readjust our national diet to match that of the turn of the century, at least as the Department of Agriculture had guessed it to be. The less controversial recommendations of the Dietary Goals included eating less sugar and salt, and more fruits, vegetables, and whole grains.

Fat and cholesterol would be the contentious points. Here Mottern avoided the inherent ambiguities of the evidence by relying for his expertise almost exclusively on a single Harvard nutritionist, Mark Hegsted, who by his own admission was an extremist on the dietary-fat issue. Hegsted had studied the effect of fat on cholesterol levels in the early 1960s, first with animals and then, like Keys, with schizophrenic patients at a mental hospital. Hegsted had come to believe unconditional y that eating less fat would prevent heart disease, although he was aware that this conviction was not shared by other investigators working in the field. With Hegsted as his guide, Mottern perceived the dietary-fat controversy as a.n.a.logous to the specious industry-sponsored "controversy" over cigarettes and lung cancer, and he equated his Dietary Goals to the surgeon general's legendary 1964 report on smoking and health. To Mottern, the food industry was no different from the tobacco industry in its wil ingness to suppress scientific truth in the interests of greater profits. He believed that those scientists who lobbied actively against dietary fat, like Hegsted, Keys, and Stamler, were heroes.

Dietary Goals was couched as a plan for the nation, but these goals obviously pertained to individual diets as wel . Goal number one was to raise the consumption of carbohydrates until they const.i.tuted 5560 percent of the calories consumed. Goal number two was to decrease fat consumption from approximately 40 percent, then the national average, to 30 percent of al calories, of which no more than a third should come from saturated fats. The report acknowledged that no evidence existed to suggest that reducing the total fat content of the diet would lower blood-cholesterol levels, but it justified its recommendation on the basis that, the lower the percentage of dense fat calories in the diet, the less likely people would be to gain weight,*14 and because other health a.s.sociations-most notably the American Heart a.s.sociation-were recommending 30 percent fat in diets. To achieve this low-fat goal, according to the Dietary Goals, Americans would have to eat considerably less meat and dairy products.

Though the Dietary Goals admitted the existence of a scientific controversy, it also insisted that Americans had nothing to lose by fol owing the advice.

"The question to be asked is not why should we change our diet but why not?" explained Hegsted at a press conference to announce publication of the doc.u.ment. "There are [no risks] that can be identified and important benefits can be expected." But this was stil a hugely debatable position among researchers. After the press conference, as Hegsted recal ed, "al hel broke loose.... Practical y n.o.body was in favor of the McGovern recommendations."

Having held one set of hearings before publis.h.i.+ng the Dietary Goals, McGovern responded to the ensuing uproar with eight fol ow-up hearings. Among those testifying was Robert Levy, director of the National Heart, Lung, and Blood Inst.i.tute, who said that no one knew whether lowering cholesterol would prevent heart attacks, which was why the NHLBI was spending several hundred mil ion dol ars to study the question. ("Arguments for lowering cholesterol through diet," Levy had written just a year earlier, even in those patients who were what physicians would cal coronary-p.r.o.ne, "remain primarily circ.u.mstantial.") Other prominent investigators, including Pete Ahrens and the University of London cardiologist Sir John McMichael, also testified that the guidelines were premature, if not irresponsible. The American Medical a.s.sociation argued against the recommendations, saying in a letter to the committee that "there is a potential for harmful effects for a radical long term dietary change as would occur through adoption of the proposed national goals." These experts were sandwiched between representatives from the dairy, egg, and cattle industries, who also vigorously opposed the guidelines, for obvious reasons. This juxtaposition served to taint the legitimacy of the scientific criticisms.

The committee published a revised edition of Dietary Goals later that year, but with only minor revisions. Now the first recommendation was to avoid being overweight. The committee also succ.u.mbed to pressure from the livestock industry and changed the recommendation that Americans "decrease consumption of meat" to one that said to "decrease consumption of animal fat, and choose meats, poultry, and fish which wil reduce saturated fat intake."

The revised edition also included a ten-page preface that attempted to justify the committee's dietary recommendations in light of the uproar that had fol owed. It included a caveat that "some witnesses have claimed that physical harm could result from the diet modifications recommended in this report...." But McGovern and his col eagues considered that unlikely: "After further review, the Select Committee stil finds that no physical or mental harm could result from the dietary guidelines recommended for the general public." The preface also included a list of five "important questions, which are currently being investigated." The first was a familiar one: "Does lowering the plasma cholesterol level through dietary modification prevent or delay heart disease in man?"

This question would never be answered, but it no longer seemed to matter. McGovern's Dietary Goals had turned the dietary-fat controversy into a political issue rather than a scientific one, and Keys and his hypothesis were the beneficiaries. Now administrators at the Department of Agriculture and the National Academy of Sciences felt it imperative to get on the record.

At the USDA, Carol Foreman was the driving force. Before her appointment in March 1977 as an a.s.sistant secretary of agriculture, Foreman had been a consumer advocate, executive director of the Consumer Federation of America. Her instructions from President Jimmy Carter at her swearing-in ceremony were to give consumers a "strong, forceful, competent" spokeswoman within the USDA. Foreman believed McGovern's Dietary Goals supported her conviction that "people were getting sick and dying because we ate too much," and she believed it was inc.u.mbent on the USDA to turn McGovern's recommendations into official government policy. Like Mottern and Hegsted, Foreman was undeterred by the scientific controversy. She believed that scientists had an obligation to take their best guess about the diet-disease relations.h.i.+p, and then the public had to decide. "Tel us what you know, and tel us it's not the final answer," she would tel scientists. "I have to eat three times a day and feed my children three times a day, and I want you to tel me what your best sense of the data is right now."

The "best sense of the data," however, depends on whom you ask. The obvious candidate in this case was the Food and Nutrition Board of the National Academy of Sciences, which determines Recommended Dietary Al owances, the minimal amount of vitamins and minerals required in a healthy diet, and was established in 1940 to advise the government on nutrition issues. The NAS and USDA drafted a contract for the Food and Nutrition Board to evaluate the recommendations in the Dietary Goals, according to Science, but Foreman and her USDA col eagues "got wind" of a speech that Food and Nutrition Board Chairman Gilbert Leveil e had made to the American Farm Bureau Federation and pul ed back. "The American diet," Leveil e had said, "has been referred to as...'disastrous'.... I submit that such a conclusion is erroneous and misleading. The American diet today is, in my opinion, better than ever before and is one of the best, if not the best, in the world today." NAS President Philip Handler, an expert on human and animal metabolism, had also told Foreman that McGovern's Dietary Goals were "nonsense," and so Foreman turned instead to the NIH and the Food and Drug Administration, but the relevant administrators rejected her overtures. They considered the Dietary Goals a "political doc.u.ment rather than a scientific doc.u.ment,"

Foreman recal ed; NIH Director Donald Fredrickson told her "we shouldn't touch it with a ten-foot pole; we should let the crazies on the hil say what they wanted."

Final y, it was agreed that the USDA and the Surgeon General's Office would draft official dietary guidelines. The USDA would be represented by Mark Hegsted, whom Foreman had hired to be the first head of the USDA's Human Nutrition Center and to shepherd its dietary guidelines into existence.

Hegsted and J. Michael McGinnis from the Surgeon General's Office relied almost exclusively on a report by a committee of the American Society of Clinical Nutrition that had a.s.sessed the state of the relevant science, although with the expressed charge "not to draw up a set of recommendations."

Pete Ahrens chaired the committee, along with Wil iam Connors of the University of Oregon Health Sciences Center, and it included nine scientists covering a "ful range of convictions" in the various dietary controversies. The ASCN committee concluded that saturated-fat consumption was probably related to the formation of atherosclerotic plaques, but the evidence that disease could be prevented by dietary modification was stil unconvincing.*15 The report described the spread of opinions on these issues as "considerable." "But the clear majority supported something like the McGovern committee report," according to Hegsted. On that basis, Hegsted and McGinnis produced the USDA Dietary Guidelines for Americans , which was released to the public in February 1980.

The Dietary Guidelines also acknowledged the existence of a controversy, suggesting that a single dietary recommendation might not be appropriate for an entire diverse population. But it stil declared in bold letters on its cover that Americans should "Avoid Too Much Fat, Saturated Fat, and Cholesterol." (The Dietary Guidelines did not define what was meant by "too much.") Three months later, Philip Handler's Food and Nutrition Board released its own version of the guidelines-Toward Healthful Diets. It concluded that the only reliable dietary advice that could be given to healthy Americans was to watch their weight and that everything else, dietary fat included, would take care of itself. The Food and Nutrition Board promptly got "excoriated in the press," as one board member described it. The first criticisms attacked the board for publis.h.i.+ng recommendations that ran counter to those of the USDA, McGovern's committee, and the American Heart a.s.sociation, and so were seen to be irresponsible. They were fol owed by suggestions that the board members, in the words of Jane Brody, who covered the story for the New York Times, "were al in the pocket of the industries being hurt." The board director, Alfred Harper, chairman of the University of Wisconsin nutrition department, consulted for the meat industry. The Was.h.i.+ngton University nutritionist Robert Olson, who had worked on fat and cholesterol metabolism since the 1940s, consulted for the Egg Board, which itself was a USDA creation to sponsor research, among other things, on the nutritional consequences of eating eggs. Funding for the Food and Nutrition Board came from industry donations to the National Academy of Sciences. These industry connections were first leaked to the press from the USDA, where Hegsted and Foreman suddenly found themselves vigorously defending their own report to their superiors, and from the Center for Science in the Public Interest, a consumer-advocacy group run by Michael Jacobson that was now dedicated to reducing the fat and sugar content of the American diet. (As the Los Angeles Times later observed, the CSPI "embraced a low-fat diet as if it was a holy writ.") The House Agriculture Subcommittee on Domestic Marketing promptly held hearings in which Henry Waxman, chairman of the Health Subcommittee, described Toward Healthful Diets as "inaccurate and potential y biased" as wel as "quite dangerous." Hegsted was among those who testified, saying "he failed to see how the Food and Nutrition Board had reached its conclusions."

Philip Handler testified as wel , summarizing the situation memorably. When the hearings were concluded, he said, the committee members might find themselves confronted by a dilemma. They might conclude, "as some have," that there exists a "thinly linked, if questionable, chain of observations"

connecting fat and cholesterol in the diet to cholesterol levels in the blood to heart disease: However tenuous that linkage, however disappointing the various intervention trials, it stil seems prudent to propose to the American public that we not only maintain reasonable weights for our height, body structure and age, but also reduce our dietary fat intakes significantly, and keep cholesterol intake to a minimum. And, conceivably, you might conclude that it is proper for the federal government to so recommend.

On the other hand, you may instead argue: What right has the federal government to propose that the American people conduct a vast nutritional experiment, with themselves as subjects, on the strength of so very little evidence that it wil do them any good?

Mr. Chairman, resolution of this dilemma turns on a value judgment. The dilemma so posed is not a scientific question; it is a question of ethics, morals, politics. Those who argue either position strongly are expressing their values; they are not making scientific judgments.

Though the conflict-of-interest accusations served to discredit the advice proffered in Toward Healthful Diets, the issue was not nearly as simple as the media made it out to be and often stil do. Since the 1940s, nutritionists in academia had been encouraged to work closely with industry. In the 1960s, this col aborative relations.h.i.+p deteriorated, at least in public perception, into what Ralph Nader and other advocacy groups would consider an "unholy al iance." It wasn't always.

As Robert Olson explained at the time, he had received over the course of his career perhaps $10 mil ion in grants from the USDA and NIH, and $250,000 from industry. He had also been on the American Heart a.s.sociation Research Committee for two decades. But when he now disagreed with the AHA recommendations publicly, he was accused of being bought. "If people are going to say Olson's corrupted by industry, they'd have far more reason to cal me a tool of government," he said. "I think university professors should be talking to people beyond the university. I believe, also, that money is contaminated by the user rather than the source. Al scientists need funds."

Scientists were believed to be free of conflicts if their only source of funding was a federal agency, but al nutritionists knew that if their research failed to support the government position on a particular subject, the funding would go instead to someone whose research did. "To be a dissenter was to be unfunded because the peer-review system rewards conformity and excludes criticism," George Mann had written in The New England Journal of Medicine in 1977. The NIH expert panels that decide funding represent the orthodoxy and wil tend to perceive research interpreted in a contrarian manner as unworthy of funding. David Kritchevsky, a member of the Food and Nutrition Board when it released Toward Healthful Diets, put it this way: "The U.S. government is as big a pusher as industry. If you say what the government says, then it's okay. If you say something that isn't what the government says, or that may be paral el to what industry says, that makes you suspect."

Conflict of interest is an accusation invariably wielded to discredit those viewpoints with which one disagrees. Michael Jacobson's Center for Science in the Public Interest had publicly exposed the industry connections of Fred Stare, founder and chair of the department of nutrition at Harvard, primarily because Stare had spent much of his career defending industry on food additives, sugar, and other issues. "In the three years after Stare told a Congressional hearing on the nutritional value of cereals that 'breakfast cereals are good foods,'" Jacobson had written, "the Harvard School of Public Health received about $200,000 from Kel ogg, Nabisco, and their related corporate foundations." Stare defended his industry funding with an aphorism he repeated often: "The important question is not who funds us but does the funding influence the support of truth." This was reasonable, but it is always left to your critics to decide whether or not your pursuit of truth has indeed been compromised. Jeremiah Stamler and the CSPI held the same opinions on what was healthy and what was not, and Stamler consulted for CSPI, so Stamler's al iance with industry-funding from corn-oil manufacturers-was not considered unholy. (By the same token, advocacy groups such as Jacobson's CSPI are rarely if ever accused of conflicts of interest, even though their entire reason for existence is to argue one side of a controversy as though it were indisputable. Should that viewpoint turn out to be incorrect, it would negate any justification for the existence of the advocacy group and, with it, the paychecks of its employees.) When I interviewed Mark Hegsted in 1999, he defended the Food and Nutrition Board, although he hadn't done so in 1979, when he was defending his own report and his own job to Congress. In 1981, when the Reagan administration closed down Hegsted's Human Nutrition Center at the USDA and found no further use for his services, Hegsted returned to Harvard, where the research he conducted until his retirement was funded by Frito-Lay. By that time, the controversy over the Food and Nutrition Board's conflicts of interest had successful y discredited Toward Healthful Diets, and Hegsted's Dietary Guidelines for America had become the official government statement on the dangers of fat and cholesterol in our diet.

Once politics, the public, and the press had decided on the benefits of low-fat diets, science was left to catch up. In the early 1970s, when NIH administrators opted to forgo a $1 bil ion National Diet-Heart Study that might possibly be definitive and to concentrate instead on a half-dozen studies, at a third of the cost, they believed the results of these smal er studies would be sufficiently persuasive to conclude publicly that low-fat diets would prolong lives. The results of these studies were published between 1980 and 1984.

Four of these studies tried to establish relations.h.i.+ps between dietary fat and health within populations-in Honolulu, Puerto Rico, Chicago (Stamler and Shekel e's second Western Electric study), and Framingham, Ma.s.sachusetts. None of them succeeded. In Honolulu, the researchers fol owed seventy-three hundred men of j.a.panese descent and concluded that the men who developed heart disease seemed to eat slightly more fat and saturated fat than those who didn't, but the men who died seemed to eat slightly less fat and slightly less saturated fat than those who didn't. This observation was made in Framingham and Puerto Rico as wel . In 1981, investigators from the three studies published an article in the journal Circulation discussing the problem.

They said it posed a dilemma for dietary advice, but not an insurmountable one. The fact that the men in Puerto Rico and Honolulu who remained free of heart disease seemed to eat more starches suggested that it might be a good idea to recommend that we al eat more starch, as McGovern's Dietary Goals actual y had. And because the advice should never be to eat more calories, we would have to eat less fat to avoid gaining weight.

When one is reading this report, it's hard to avoid the suspicion that once the government began advocating fat reduction in the American diet it changed the way many investigators in this science perceived their obligations. Those who believed that dietary fat caused heart disease had always preferential y interpreted their data in the light of that hypothesis. Now they no longer felt obliged to test any hypothesis, let alone Keys's. Rather, they seemed to consider their obligation to be that of "reconciling [their] study findings with current programs of prevention," which meant the now official government recommendations. Moreover, these studies were expensive, and one way to justify the expense was to generate evidence that supported the official advice to avoid fat. If the evidence didn't support the recommendations, then the task was to interpret it so that it did.*16 The other disconcerting aspect of these studies is that they suggested (with the notable exception of three Chicago studies reported by Jeremiah Stamler and col eagues) low cholesterol levels were a.s.sociated with a higher risk of cancer. This link had original y been seen in Seymour Dayton's VA Hospital trial in Los Angeles, and Dayton and others had suggested that polyunsaturated fats used to lower cholesterol might be the culprits. This was confirmed in 1972 by Swiss Red Cross researchers. In 1974, the princ.i.p.al investigators of six ongoing population studies-including Keys, Stamler, Wil iam Kannel of Framingham, and the British epidemiologist Geoffrey Rose-reported in The Lancet that the men who had developed colon cancer in their populations had "surprisingly" low levels of cholesterol, rather than the higher levels that they had initial y expected. In 1978, a team of British, Hungarian, and Czech researchers reported similar findings from a sixteen-thousand-man clinical trial of a cholesterol-lowering drug. By 1980, this link between cancer and low cholesterol was appearing in study after study. The most consistent a.s.sociation was between colon cancer and low cholesterol in men. In the Framingham Study those men whose total cholesterol levels were below 190 mg/dl were more than three times as likely to get colon cancer as those men with cholesterol greater than 220; they were almost twice as likely to contract any kind of cancer than those with cholesterol over 280 mg/dl.

This finding was met with "surprise and chagrin," Manning Feinleib, a National Heart, Lung, and Blood Inst.i.tute (NHLBI) epidemiologist, told Science.

This a.s.sociation was considered sufficiently troublesome that the NHLBI hosted three workshops between 1980 and 1982 to discuss it. In this case, however, the relevant administrators and investigators did not consider it sufficient to pay attention only to the positive evidence (that low cholesterol was a.s.sociated with an increased risk of cancer even in clinical trials) and reject the negative evidence as irrelevant or erroneous, as they had when implicating high cholesteral as a cause of heart disease. Instead, they searched the literature and found a few studies-including a Norwegian study published a decade earlier in a Scandinavian journal supplement-that reported no link between low cholesterol and cancer. As a result, the NHLBI concluded that the evidence was inconsistent, only "suggestive" that "low cholesterol may be in some way a.s.sociated with cancer risk," said Robert Levy after the first workshop. After the second workshop, by which time the Framingham, Honolulu, and Puerto Rico studies had reported the same a.s.sociation, the NHLBI administrators stil considered the results inconclusive: "The findings do not represent a public health chal enge; however, they do present a scientific chal enge," they wrote. Levy did tel the journal Science that this low-cholesterol/cancer link might make those investigators who were arguing that everyone's cholesterol should be as low as possible "a little more cautious."

After the third workshop, Levy and his NHLBI col eagues concluded that the evidence stil didn't imply cause and effect. They believed that high cholesterol caused heart disease and that low cholesterol was only a sign of people who might be cancer-p.r.o.ne, perhaps because of a genetic predisposition. This seemed like an arbitrary distinction, and it was certainly based on a.s.sumptions more than facts. The NHLBI administrators acknowledged that further research would be necessary to clarify "the perplexing inconsistencies." Stil , the evidence did "not preclude, countermand, or contradict the current public health message which recommends that those with elevated cholesterol levels seek to lower them through diets."

In the early 1970s, the National Heart, Lung, and Blood Inst.i.tute had bet its heart-disease prevention budget on two enormous trials that held out hope of resolving the controversy.

The first was the Multiple Risk Factor Intervention Trial, known as MRFIT and led by Jeremiah Stamler. The goal of MRFIT was to "throw the kitchen sink" at heart disease: to convince the subjects to quit smoking, lower their cholesterol, and lower their blood pressure-the multiple-risk-factor interventions. The MRFIT investigators tested the cholesterol of 362,000 middle-aged American men and found twelve thousand (the top 3 percent) whose cholesterol was so high, more than 290 mg/ml, that they could be considered at imminent risk of having a heart attack. The MRFIT investigators believed that these men were so likely to succ.u.mb to heart disease that preventive measures would be even more likely to demonstrate a benefit. (If men with lower cholesterol were included, or if women were included, the study would require a considerably greater number of subjects or a longer fol ow-up to demonstrate any significant benefit.) These twelve thousand men were randomly divided between a control group-told to live, eat, and address their health problems however they desired-and a treatment group-advised to quit smoking, take medication to lower their blood pressure if necessary, and eat a low-fat, low-cholesterol diet, which meant drinking skim milk, using margarine instead of b.u.t.ter, eating only one or two eggs a week, and avoiding red meat, cakes, puddings, and pastries. Al twelve thousand were then fol owed for seven years, at a cost of $115 mil ion.

The results were announced in October 1982, and a Wall Street Journal headline captured the situation succinctly: "Heart Attacks: A Test Col apses."

There had been slightly more deaths among those men who had been counseled to quit smoking, eat a cholesterol-lowering diet, and treat their high blood pressure than among those who had been left to their own devices.*17 The second trial was the $150 mil ion Lipid Research Clinics (LRC) Coronary Primary Prevention Trial. The trial was led by Basil Rifkind of the NHLBI and Daniel Steinberg, a specialist on cholesterol disorders at the University of California, San Diego. The LRC investigators had screened nearly half a mil ion middle-aged men and found thirty-eight hundred who had no overt signs of heart disease but cholesterol levels sufficiently high-more than 265 mg/dl-that they could be considered imminently likely to suffer a heart attack. Half of these men (the control group) were told to eat fewer eggs and less fatty meats and drink less milk, and were given a placebo pil to take daily. The other half (the treatment group) were counseled to eat the same cholesterol-lowering diet, but they were also given a cholesterol-lowering drug cal ed cholestyramine. Both groups had been told to diet, because the LRC investigators considered it unethical to withhold al treatment from the control group, given their high cholesterol levels and high risk of heart disease. It was an odd decision for two reasons. First, the LRC trial had been approved in the early 1970s in lieu of the National Diet-Heart Study that was necessary to establish the safety and effectiveness of a cholesterol-lowering diet; the LRC investigators had no proof that such a diet would benefit their subjects, rather than harm them. Second, both groups were told to diet, the trial could determine only the effectiveness of the drug-the single variable that differed between them.

In January 1984, the results of the trial were published in The Journal of the American Medical a.s.sociation. Cholesterol levels dropped by an average of 4 percent in the control group-those men taking a placebo. The levels dropped by 13 percent in the men taking cholestyramine. In the control group, 158 men suffered nonfatal heart attacks during the study and 38 men died from heart attacks. In the treatment group, 130 men suffered nonfatal heart attacks and only 30 died from them. Al in al , 71 men had died in the control group and 68 in the treatment group. In other words, cholestyramine had improved by less than .2 percent the chance that any one of the men who took it would live through the next decade. To cal these results "conclusive," as the University of Chicago biostatistician Paul Meier remarked, would const.i.tute "a substantial misuse of the term." Nonetheless, these results were taken as sufficient by Rifkind, Steinberg, and their col eagues so they could state unconditional y that Keys had been right and that lowering cholesterol would save lives.

Rifkind and his col aborators also concluded that the cholesterol-lowering benefits of a drug applied to diet as wel . Although the trial included only middle-aged men with cholesterol levels higher than those of 95 percent of the population, Rifkind and his col eagues concluded that those benefits "could and should be extended to other age groups and women and...other more modest elevations of cholesterol levels." As Rifkind told Time magazine, "It is now indisputable that lowering cholesterol with diet and drugs can actual y cut the risk of developing heart disease and having a heart attack."

Pete Ahrens cal ed this extrapolation from a drug study to a diet "unwarranted, unscientific and wishful thinking." Thomas Chalmers, an expert on clinical trials who would later become president of the Mt. Sinai School of Medicine in New York, described it to Science as an "unconscionable exaggeration of al the data." In fact, the LRC investigators acknowledged in their JAMA article that their attempt to ascertain a benefit from diet alone had failed.

Rifkind later explained the exaggerated claims. For twenty years, he said, those who believed in Keys's hypothesis had argued that lowering cholesterol would prevent heart attacks. They had spent hundreds of mil ions of dol ars trying to prove it, in the face of extreme skepticism. Now they had demonstrated that lowering cholesterol had reduced heart-disease risk and maybe even saved lives. They could never prove that cholesterol-lowering diets would do the same-that would be too expensive, and MRFIT, which might have implied such a conclusion, had failed-but now they had established a fundamental link in the causal chain from lower cholesterol to cardiovascular health. With that, they could take the leap of faith from cholesterol-lowering drugs to cholesterol-lowering diets. "It's an imperfect world," Rifkind said. "The data that would be definitive is ungettable, so you do your best with what is available."

With publication of the LRC results, the National Heart, Lung, and Blood Inst.i.tute launched what Robert Levy cal ed "a ma.s.sive health campaign" to convince the public of the benefits of lowering cholesterol, whether by diet or drug, and the media went along. Time reported the LRC findings in a story headlined "Sorry, It's True. Cholesterol Real y Is a Kil er." The article about a drug trial began, "No whole milk. No b.u.t.ter. No fatty meats. Fewer eggs..." In March, Time ran a fol ow-up cover story quoting Rifkind as saying that the LRC results "strongly indicate that the more you lower cholesterol and fat in your diet, the more you reduce your risk of heart disease." Anthony Gotto, president of the American Heart a.s.sociation, told Time that if everyone went along with a cholesterol-lowering program, "we wil have [atherosclerosis] conquered" by the year 2000.

The fol owing December, the National Inst.i.tutes of Health hosted a "consensus conference" and effectively put an end to thirty years of debate. Ideal y, in a consensus conference an unbiased expert panel listens to testimony and arrives at conclusions on which everyone agrees. In this case, Rifkind chaired the planning committee, of which Steinberg was a member. Steinberg was then chosen to head the expert panel that would draft the consensus. The twenty speakers did include three skeptics-Ahrens, Robert Olson, and Michael Oliver, a cardiologist with the Medical Research Council in London-who argued that the wisdom of a cholesterol-lowering diet could not be established on the strength of a drug experiment, let alone one with such borderline results. A month after the conference, the NHLBI epidemiologist Salim Yusuf described the controversy to Science as remaining as polarized as ever: "Many people have already made up their minds that cholesterol-lowering helps, and they don't need any evidence. Many others have decided that cholesterol-lowering is not helpful, and they don't need any evidence either."

March 1984: the results of a drug trial are translated into the message that fatty foods will cause heart disease. (Time magazine 1984 Time Inc. Reprinted by permission.) But this was not the message of Steinberg's "consensus" panel, which was composed exclusively of lay experts and clinical investigators who "were selected to include only [those] who would, predictably, say that al levels of blood cholesterol in the United States are too high and should be lowered," as Oliver wrote in a Lancet editorial fol owing the conference. "And, of course, this is exactly what was said." Indeed, the consens