Fat land : how Americans became the fattest people in the world (14 page)

Andres then assessed twenty-three weight studies of other populations, ranging from Japanese men in Hawaii to American Indians. "We compared the body mass indices associated with the lowest mortality from these studies with the body mass indices of the Metropolitan tables," he wrote. Again, the results seemed revolutionary. Higher weights were associated with lower rates of death, particularly among persons over age forty. The recommended weights were thus "too restrictive." A forty-year-old could thus be up to 20 percent fatter than previously thought and still be at minimum added risk from weight-related death. In December 1985 Andres published his findings in the prestigious Annals of Internal Medicine. He then embarked on an

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extensive lobbying effort to change the USDA's weight guidelines, speaking frequently at gatherings of public health experts, advocates for the elderly, and various special-interest groups.

Andres was certainly on to something. The goal of crafting weight guidelines that more closely reflect America's racial and ethnic diversity was a righteous one. For decades, even conservative scholars of actuarial data knew that their subject pool, like Cooper's data on rich executive exercisers, was unrepresentative of the national experience. The problem was getting good data on those populations — data that were both statistically and medically sound. Unfortunately, Andres had erred on both those counts — erred badly. Yet for two years he went unchallenged, his conclusions slowly but surely taking hold in the national consciousness. Anti-diet and fat rights groups cited him regularly in discussions of why being fat wasn't really a problem. Feminists concerned about anorexia took heart in the notion that the good fight was not against fat but against "unrealistic leanness." It was okay to gain weight.

Then in 1987 four scholars from Harvard University's School of Public Health, led by Walter Willett and Meir Stampfer, dropped a bomb on Andres's research. Trained in epidemiology as well as diabetes and obesity, the quartet closely examined twenty-five of the major prospective studies on body weight and longevity, including the 1979 Metropolitan Life Build Study, the cornerstone of Andres's work. If Andres had been surprised by his reworking of the numbers, the Harvardites were downright frightened by their own. In each and every study they found biases that were so severe and substantial that "failure to address any one issue will lead to an underestimate of excess mortality associated with being overweight." The biases led, they concluded in the Journal of the American Medical Association, to a "systematic underestimate of the impact of obesity on premature mortality." It was not okay to gain weight as one aged.

These were fighting words. But Willett and Stampfer had done their homework. Perhaps the most egregious flaw in most of the

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studies was their authors' failure to control for cigarette smoking, which is an independent risk factor that is more prevalent among the lean than the fat. (Smoking inhibits caloric intake and increases metabolic rates and energy expenditure.) Thus, to get an accurate picture of the added risk of premature death from excess weight, one must "deduct" the effect of smoking. If the statistician does not do this, Willett and Stampfer argued, one comes away with an artificially high mortality rate in lean subjects. That makes being heavier look less risky when it is actually more so.

This was not mere academic nitpicking. Controlling for independent risk factors is a widely accepted — indeed required — protocol in modern epidemiology. Willett and Stampfer had done just that. The results: "After controlling for smoking," they wrote, "the risk of death . . . increased by two percent for each pound of excess weight for ages 50 to 62, and by one percent per extra pound for ages 30 to 49." The same conclusion was reached after reanalyzing an American Cancer Society survey of 750,000 men and women: There was no basis for recommending more lenient weight guidelines. In fact, the numbers suggested just the opposite: Weight guidelines needed to be stricter. Stating the obvious in the face of denial and wishful thinking, Willett and Stampfer noted that "few in the general U.S. population are at an increased risk of death from excessive leanness."

By the time Willett and Stampfer had published their work, however, the "Andres thesis," as it became known, had gathered speed and weight. The notion that excessive leanness was the problem and that overly severe weight guidelines were unfair played to the decade's overwrought identity politics, to concerns about gender, race, ethnicity, and age. In the academy and on the street, people heard what they wanted to hear, and what they wanted to hear was that it was okay to be fatter. And by the time the USDA's Dietary Guidelines Committee met in 1989, what the people wanted to hear had fused with the professional agenda of some of the nation's leading public health scholars.

The personification of that fusion was Dr. C. Wayne Callaway,

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an esteemed Washington, D.C., physician and public health expert. Callaway had been appointed by the Dietary Guidelines Committee to spearhead an inquiry into weight guidelines. Easygoing, witty, charming, and agile in the logic department, Callaway quickly made his charge a forum for his own inclinations on a wide range of weight-related issues. This was not unusual; most appointees to most public bodies do the same thing, sometimes overtly, sometimes not so. And for the most part, Callaway was on target. It was Callaway who argued for and won one of the most important changes in the guidelines — the inclusion of fat distribution patterns as a key determinate of weight-related risk. As he liked to say, "I can line up ten people, all of the same height and weight, and the fat deposition patterns will be all over the place. What the science shows is that the ones who look more like a pear — who carry their excess weight on their hips — are not as unhealthy as those who look like an apple — the ones who carry the excess fat on their belly." For the first time, Americans were instructed exactly how to calculate their waist-to-hip ratio — an important piece of information when determining whether one should lose weight or not.

But the waist-to-hip ratio also illustrated Callaway's one weakness: a tendency to want to salve too many special constituencies. The ratio was not only medically important, he argued in committee meetings. It was also socially just. Using simplistic weight-for-height tables, he said, "lets men off the hook too easily" (because they carry their excess weight in their belly) while simultaneously discriminating against women (who tend to carry their excess weight in their hips). To make them both use the same table caused women to worry too much and gave men "too much balm." Callaway's understanding of women as a group needing, in some areas, its own health guidelines was sound, but from here his tendency to placate constituencies began to separate him from the data.

There was, for instance, his concern about excessive dieting, a legitimate (albeit epidemiologically small) issue that colored

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other, more substantive concerns about obesity. In discussing one section about weight control, he interjected, to the surprise of his colleagues, that the committee should leave out the statement "One thing is definite. To lose weight, you must take in fewer calories than you burn." To Callaway, such a statement was "authoritarian." He went on: "What is hidden in that is blaming the victim. There are thousands and thousands of people who are chronically dieting, and if they take in fewer calories, it doesn't help them." At this even his usually sympathetic colleague University of California at Davis nutrition scholar Barbara Schnee-man interjected: "But that concept still has to be conveyed to people, that ultimately it is caloric balance that will determine weight loss!"

Anorexia and bulimia, also legitimate (and also epidemio-logically small) health issues, were also accorded undue emphasis. "Because if we look at certain subsegments of the population," Callaway went on, "as has been done for instance in affluent suburban school systems . . . fourth-grade girls are already dieting and defining themselves as being overweight. So if we come back to this thing about the potential for harm, I think we really need to balance that and almost give it equal balance."

Then came the issue of age. As Callaway saw it, "By the time a woman gets to age sixty-five, only about 10 percent of women are at the quote, ideal body weight." Rather than seeing this as more evidence that Americans were growing fatter, Callaway declared it an issue of inequality. "So, again, we have this age discrimination," he said. "So again, we're using a standard which doesn't make sense to the elderly population." The answer, he said, was to revise the weight guidelines upward — a historic first in the annals of the committee.

But unlike his advocacy of waist-to-hip ratios, Callaway's age-adjusted tables rested on a single — and very shaky — leg: Reubin Andres's 1985 study. Willett and Stampfer tried to get their concerns across, but since they were not members of the committee, "our views did not get a fair shake," Stampfer says.

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Willett recalls the situation somewhat more bitterly. "As far as I am concerned," he says, that decision "was one of the worst cases of backroom dealing that I have ever seen." The committee, he says, refused to look at the smoking data, despite the then growing evidence that Andres had been wrong.

Instead, in November of 1990, the committee announced its new guidelines. As the New York Times put it, "The guideline on weight suggests that people over thirty-five can be heavier than young adults without risk to health." Andres and Callaway had triumphed. It was okay to get fatter as one aged.

For the next five years, Willett, Stampfer, and a broad swath of the nutrition community labored for better data on the subject of age and weight. Other groups in the United States and abroad, appalled by the committee's action, published new data on the age-weight link as well. Almost all came to similar conclusions: For healthy people, male or female, it is almost always better to avoid weight gain — at any age, for any reason. So convincing was the evidence that, when the committee reconvened in 1995 (sans Callaway), it unanimously voted to rescind the age guidelines. "Based on published data, there appears to be no justification for the establishment of a cut point that increases with age," the new committee wrote in a terse note. "Although the nadir of mortality curves increases with age in several studies, these studies have failed to control for a history of smoking, which appears to affect mortality at all ages." Again, it was not okay to gain weight as one got older.

Yet for five years, such was the governmental advice that Americans, experiencing the biggest increases in obesity rates ever, seem very much to have taken to heart. And waist.

Given the debacle of the early 1990s reforms, one would imagine that the American exercise establishment might think twice about proclaiming new public health messages that sanctioned sloth, gluttony, or denial. But about that one would be wrong; they did not think twice. Instead, the brightest lights of their leadership

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embarked upon another crusade, this one to convince the American public that they should not focus on fat at all — that they should forget about dieting and losing weight and instead learn how to be "fit and fat."

The gladiator of the crusade is Steven Blair, a brilliant Texas epidemiologist, director of the Cooper Institute, and himself a leading proponent of the health-based fitness recommendations of the 1980s. For two decades, Blair has been at the primordial center of the debate about fitness. It has also been something of a personal issue for him. He is, as he likes to say, "Fat, fit, and bald

— and none of those things are likely to change."

For years Blair did try to change; in the 1980s he followed a strict diet — the one recommended by the AMA — but to little avail. Like some obese people, his body is in thrall to a stronger genetic inclination to retain excess weight. Unlike most obese people, Blair's response to his birthright has been to get tougher

— he is a marathoner, triathlete, and vigorous sportsman. He has run, by his own estimate, more than 80,000 miles over the past thirty years. With his confident, engaging manner, mile-long vita, and persuasive debate style, Blair is his own best advertisement for his fit and fat campaign. And campaign he does. "We've got to get rid of this focus on weight," he likes to say at every media interview. "There's a misdirected focus on weight and weight loss — the focus is all wrong. It's fitness that's the key." Or: "Let's throw away all the scales. Let's stop talking about weight." At times he goes even further, proclaiming that "you can stay overweight and obese if you are fit and be just as healthy, in terms of mortality risk, as a lean fit person."

As usual, the scientific basis for Blair's case rests on studies of clients of the Cooper Institute — white, affluent, male professionals who had come to the center for a medical exam between 1970 and 1989. In Blair's clinical measure of their health, the key variable was fitness as assessed on a treadmill test. The test starts at a speed of eighty-eight meters a minute at zero elevation, which is increased to 2 percent elevation for the second minute, then 1

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percent each minute to twenty-five minutes; after that researchers turn up the speed every minute until the test is halted when the subject becomes exhausted. Since total time on a treadmill correlates strongly with individual fitness levels, Blair was then able to assign participants to different, age-group-specific fitness categories — low fit, moderate fit, and high fit. He next calculated in BMI — a weight-for-height index based on health outcomes rather than on "what is normal" — thereby creating three distinct groups to study: normal weight men with low, medium, and high fitness rates; overweight men with low, medium, and high fitness rates; and obese men with low, medium, and high fitness rates.

To find out what all this meant, Blair then figured in the rate of death and related risks that took place within this group over the years. What he found was important. Death rates were inversely related to fitness status. While it wasn't too surprising that high-fit, normal-weight men had death rates 61 percent lower than low-fit men, it was notable that the risk reduction held up when applied to fat men who were in the fit — or high treadmill time — category. The conclusion, in its invariable unexciting academese, was that "inverse gradients of mortality across fitness groups were similar for obese and non-obese men." Blair, however, spun it like this: Fat men who were fit lived longer than slim men who were not fit.