31st July, 2004. www.smh.com.au
Quote:
A big fat con
By: Paul Campos
Size really doesn't matter. You can be just as healthy if you're roly-poly as you can if you're slender, no matter what the fat police may say. Or so argues Paul Campos in this extract from his provocative new book, The Obesity Myth.
In January 2003, as America prepared to go to war with Iraq, the US surgeon general, Richard Carmona, warned the nation that it faced a far more dangerous threat than Saddam Hussein's supposed weapons of mass destruction. Rather than focusing on the danger posed by nuclear, biological and chemical weapons, Carmona told his audience, "Let's look at a threat that is very real, and already here: obesity."
Carmona is merely the latest in a series of surgeon generals who have treated America's expanding waistline as the nation's leading public health problem. In doing so, they have merely reflected the language of much of the medical establishment, which for decades has treated "overweight" and "obesity" as major health risks.
Fat is on trial, but until now the defence has been mostly absent from the court of public opinion. At bottom, the case against fat rests on the claim that the thinner you are, the longer you will live. Fat kills, we're told, and the prescription is clear: get thin.
The doctors and public health officials prosecuting the war on fat would have us believe that who is or isn't fat is a scientific question that can be answered by consulting something as crude as a body mass index chart (the BMI is a mathematical formula that puts people of different heights and weights on a single integrated scale). This, like so many other claims at the heart of the case against fat, is false. "Fat" is a cultural construct. According to the public health establishment's current BMI definitions, Brad Pitt, Michael Jordan and Mel Gibson are all "overweight", while Russell Crowe and George Clooney are both "obese". According to America's fat police, if your BMI is over 25, then you are overweight, full stop. Note also the radical difference between how our culture defines fashionable thinness for men and women. If Jennifer Aniston had the same BMI as her husband Brad Pitt, she would weigh approximately 25 kilograms more than she does.
According to the latest BMI figures, 64.5 per cent of American adults are either overweight (meaning they have a BMI of between 25 and 29.9) or obese (defined as a BMI of 30 or higher). (The latest Australian figures show 67 per cent of adult males and 52 per cent of adult women as either overweight or obese.) Studies have found an association between even mild amounts of excess weight and a significantly increased risk of premature death. For example, a highly publicised study published in The New England Journal of Medicine in 1995 found that women of average height who were as little as 12lb (5.4kg) overweight had a 60 per cent increased risk of mortality. A 1999 study published in The Journal of the American Medical Association (JAMA) estimated that excess weight led to about 300,000 premature deaths a year in America alone.
Meanwhile, the proportion of the population that maintains a dangerously high weight continues to climb: obesity in America has increased by more than 50 per cent over the past decade. If the authors of these studies are correct, America is facing a health crisis that, in the words of one anti-fat warrior, will make AIDS look "like a bad case of the flu".
The Centres for Disease Control warn that overweight and obesity put people at increased risk for congestive heart failure, coronary heart disease, diabetes, high blood pressure, obstructive sleep apnoea and other respiratory problems, and some cancers. The case against fat thus seems clear: having a BMI of 25 (this is a weight of 66kg for a woman of average height, and 81kg for a man of average height) or higher has been proven by medical science to cause myriad deadly conditions.
The question then becomes, what can we do about this epidemic that is putting in jeopardy the lives of the more than 135 million adult Americans who are currently overweight?
The solution to this crisis seems obvious: Americans (and those in other "fat" nations such as Britain and Australia) should find a way to weigh less. A recent article by Harvard Medical School researchers was more specific: "Adults should try to maintain a body mass index between 18.5 and 21.9 to minimise their risk of disease" (for a woman of average height, this would mean maintaining a weight between 49kg and 58kg).
How are we supposed to achieve these goals? Public health authorities assure us that the best path to healthy weight loss is a combination of caloric restriction - aka dieting - and exercise. Unfortunately, this classic prescription has an extremely high failure rate: the vast majority of dieters end up regaining all of the weight they lose, and many end up weighing more than they did prior to their attempts to lose weight. Given this record of failure, it's not surprising that the pharmaceutical industry has spent billions of dollars attempting to develop safe and effective weight-loss drugs. And for those whom neither dieting nor diet drugs can seem to help, weight-loss surgery is becoming an increasingly popular, if dangerous, option.
This, then, is the case against fat: the developed world, we are told, is on the verge of eating itself to death. The core belief of those prosecuting this case is that the BMI tables testify to a strong, predictable relationship between increasing weight and increasing mortality. That, after all, is what most people assume when they read that medical and public health authorities have determined a BMI of 25 or above is hazardous to a person's health. This belief, however, is not supported by the available evidence.
A 1996 project undertaken by scientists at the National Centre for Health Statistics and Cornell University analysed the data from dozens of previous studies, involving a total of more than 600,000 subjects with up to a 30-year follow-up. Among non-smoking white men, the lowest mortality rate was found among those with a BMI between 23 and 29, which means that a large majority of the men who lived longest were overweight according to government guidelines. The mortality rate for white men in the supposedly ideal range of 19 to 21 was the same as that for those in the 29 to 31 range (most of whom would be defined now as obese). In regard to non-smoking white women, the study's conclusions were even more striking: the BMI range correlating with the lowest mortality rate was extremely broad, from about 18 to 32, meaning a woman of average height could weigh anywhere within a 36kg range without seeing any statistically significant change in her risk of premature death.
In almost all large-scale epidemiological studies, little or no correlation between weight and health can be found for a large majority of the population - and indeed, what correlation does exist suggests that it is more dangerous to be just a little underweight than substantially overweight. So, let us look at the most cited studies for the proposition that overweight is a deadly epidemic in America today. Anyone who bothers to examine the evidence in the case against fat with a critical eye will be struck by the radical disconnection between the data in these studies and the conclusions their authors reach.
"Annual Deaths Attributable to Obesity in the United States", which appeared in JAMA in 1999, is the source for the endlessly repeated statistic that being overweight causes about 300,000 extra deaths in the US every year. (This "fact" has been cited in the major media more than 1700 times in the past two years alone.) Yet this survey reveals a very broad, U-shaped risk curve. For example, the study's data indicate that people with a BMI of 20 run the same risk of premature death as those with BMIs of 30, even though the former are ideally thin, while the latter are "obese". And both these groups have a slightly higher risk than people with a BMI of 25 ("overweight").
One would never guess from the authors' discussion of their findings, and the conclusions they reach, that their data showed little or no fluctuation in risk associated with differing body mass for the large majority of the people included in their study.
Furthermore, as Glenn Gaesser, a professor at the University of Virginia, points out, studies have consistently failed to find any correlation between increasing BMI and higher mortality in people 65 and over, and 78 per cent of the approximately 2.3 million annual deaths in the US occur among people who are at least 65. Thus, 78 per cent of all deaths lack even the beginning of a statistical link with BMI. "That leaves 500,000 annual deaths in persons under 65 that might be related to BMI," Gaesser told me. "These include deaths from every possible cause: motor vehicle and other accidents, homicides, suicides, cigarettes, alcohol, microbial agents, toxic agents, drug abuse, etc, etc. To think that 60 per cent [i.e., 300,000] of these deaths are due to body fat is absolutely preposterous."
"Overweight, Obesity and Mortality From Cancer", published in The New England Journal of Medicine in April 2003, was the subject of front-page stories in many of the US's leading newspapers. For example, a Los Angeles Times article reported that the study provided "the first definitive account of the relationship between obesity and cancer" and went on to quote the study's authors to the effect that perhaps as many as 90,000 deaths a year from cancer could be avoided if all adults maintained a BMI below 25 throughout their lives. The disjunction between this study's actual data and the alarmist headlines its authors helped generate is especially remarkable.
Among supposedly ideal weight individuals (BMI 18.5 to 24.9), the study observed a mortality rate from cancer of 4.5 deaths for every 1000 subjects. Among overweight individuals (BMI 25 to 29.9 - a category that in America currently includes about twice as many adults as the ideal weight cohort), the cancer mortality rate was 4.4 deaths for every 1000 subjects. In other words, overweight people actually had a lower overall cancer mortality rate than ideal weight individuals.
Most people, and indeed most doctors, simply assume that the heavier you are, the more likely it is you will suffer from coronary artery disease - hence the various cliches about artery-clogging fast food and the like. Yet several studies have specifically investigated the question of whether a high percentage of body fat correlates with the incidence of coronary artery disease. Answer: no, it does not. Even massively obese men and women do not appear to be more prone to vascular disease than average.
It is true that increasing weight is associated with high blood pressure and certain types of heart disease. But even here there is evidence that this correlation is not necessarily a product of being fat, but rather of losing and then regaining weight. Obese patients who have been put on very low-kilojoule diets subsequently display much higher rates of congestive heart failure than equally fat people who did not attempt to lose weight in the first place. The biggest evidentiary problem for those who insist there is a strong causal link between increasing weight and heart disease
is that deaths from heart disease have been plunging at precisely the same time that obesity rates have been skyrocketing.
Indictments in the case against fat invariably focus on diabetes, because Type 2 diabetes is much more common among heavier-than-average people. It has become routine to claim that Western society is about to be overwhelmed by a diabetes epidemic, that for the first time Type 2 diabetes is being seen among children, etc, and that the solution to this crisis is to make fat people thin. Actually, the definition of diabetes has changed (from a fasting blood sugar of 140 to a blood sugar of 126) and many more people have been diagnosed as suffering from the disease. Several recent studies indicate that the key to avoiding Type 2 diabetes is not to try to lose weight (indeed, there is much evidence that dieters are far more prone to the disease than average), but rather to make lifestyle changes in regard to activity levels and dietary content that greatly reduce the risk of contracting the disease, whether or not such changes lead to any weight loss.
Over the past three decades, according to Gaesser's survey of the literature, between 35 and 40 medical studies have found increasing body mass to be associated with a lower incidence of various cancers, and with lower mortality from cancer. Other diseases and syndromes that various medical studies indicate are less common among heavier people include emphysema, chronic obstructive pulmonary disease, hip fracture, vertebral fracture, tuberculosis, anaemia, peptic ulcer and chronic bronchitis, among others. Indeed, how many people are aware that heavier women have much lower rates of osteoporosis, which is a very common and serious condition among older women? Consider the potential implications for public health of the fact that hip fractures are 2 1/2 times less likely to occur among heavier women. Hip fracture is a leading cause of both death and permanent disability among older women (in Britain, more women die from osteoporosis-related hip fracture than from breast, cervical and uterine cancer combined).
There are some groups of heavier individuals - usually those with BMI figures in the mid-30s and above - who do suffer from worse health or shorter life expectancy than those of "ideal weight". Yet this does not of itself prove that such people's problems are caused by their excess weight. There are many other factors that disproportionately affect the heaviest people in our society, and that also correlate with poor health: most notably a sedentary lifestyle, poor diet, dieting-induced weight fluctuation, diet drug use, poverty, access to and discrimination in health care, and social discrimination generally. And yet all of the studies that are most often cited by anti-fat warriors almost completely fail to control for such factors.
The case against fat proceeds on the assumption that if a fat person becomes
thin, that person will acquire the health characteristics of people who were thin in the first place. Although this assumption may seem like simple commonsense, it is, like many commonsensical assumptions, quite dubious. If a person who is physiologically inclined to be fat loses weight, this does not transform that person into someone who is physiologically inclined to be thin.
To understand the implications of this distinction, consider that bald men die sooner, on average, than hirsute men, probably because bald men have higher levels of testosterone, which appears to lower life expectancy. Given this, surely no one would conclude that giving a bald man hair implants would improve his prospects for long life.
No one has ever successfully conducted a study into the health benefits of turning fat people into thin people, and for a very simple reason: no one knows how to turn fat people into thin people. This statement is in one sense shocking, despite the fact that there are few better established empirical propositions in the entire field of medicine. How can this be? After all, as those who prosecute the case against fat never cease to remind us, everyone knows how to lose weight: eat less and exercise more. In theory, this regimen should make people thin. In practice, it does not.
For example, in the US, more people than ever are dieting; percentages tripled over the course of the last generation. And the result? Americans weigh on average 15lb (nearly 7kg) more than they did 20 years ago. The vast majority of people who attempt to lose weight eventually gain back all the weight they lose, and sometimes more. So we simply don't know if people who lose a large amount of weight and keep it off permanently improve their health by doing so. This is what we do know: tens of millions of Americans are trying - more or less constantly - to lose 20 or 30lb (the average figure cited in surveys of dieters tends to be 25lb [11.3kg]). If you ask them why, most will tell you that they are doing so for the sake of their health, often on the advice of their doctors. Yet Gaesser notes that more than two dozen studies have found that weight loss of this magnitude leads to an increased risk of premature death, sometimes by an order of several hundred per cent.
Over the past 20 years, scientists have gathered a wealth of evidence indicating that cardiovascular and metabolic fitness, and the activity levels that promote such fitness, are far more important predictors of both overall health and mortality risk than weight.
The most extensive work in this area has been carried out by Steven Blair and his colleagues at Dallas's Cooper Institute, involving more than 70,000 people. What they have discovered is that, quite simply, when researchers take into account the activity levels and resulting fitness of the people being studied, body mass appears to have no relevance to health whatsoever. In Blair's studies, obese people who engage in at least moderate levels of physical activity have about one half the mortality rate of sedentary people who maintain supposedly ideal weight levels.
Similarly, a 1999 Cooper Institute study involving 22,000 men found the highest death rate among sedentary men with waist measurements under 34 inches (86cm), while the lowest death rate was found among fit men with waist measurements of 40 inches (102cm) or more. A 1995 Blair study found that improved fitness (i.e., going from "unfit" to "fit", with the latter requiring a level of exercise equivalent to going for a brisk half-hour walk four or five times a week) reduced subsequent mortality rates by 50 per cent. As Blair himself puts it, Americans have "a misdirected obsession with weight and weight loss. The focus is all wrong. It's fitness that is the key."
Why are we so afraid of the generally small health risks associated with above-average weight, while remaining comparatively indifferent to the much larger health risks associated with being a man, or poor, or black, or unusually thin?
Consider this: from the perspective of a profit-maximising medical and pharmaceutical industry, the ideal disease would be one that never killed those who suffered from it, that could not be treated effectively, and that doctors and their patients would nevertheless insist on treating anyway. Luckily for it, the health care industry has discovered (or rather invented) just such a disease.
It is called "obesity". Basically, obesity research is funded by the diet and drug industry - that is, the economic actors who have the most to gain from the conclusion that being fat is a disease that requires aggressive treatment. Many researchers have direct financial relationships with the companies whose products they are evaluating.
US government grant money is scarce, and the process for securing it extremely competitive. "When you apply for a grant," one prominent obesity researcher told me, "you have to make a strong case for funding by explaining the significance of the research." The researcher then asked me which of the following scenarios was most likely to produce a successful application:
1. "Though it is difficult to establish the independent contribution of obesity to morbidity and mortality, and it appears that lifestyle factors - such as poor diet and lack of physical activity - pose far greater health risks, we nevertheless request funding to study obesity as a matter of scientific curiosity, and also to assess whether it might be more prudent to get fat people fit rather than to get them thin."
Or: 2. "Obesity kills at least 300,000 Americans every year, and mathematical models of the obesity epidemic predict that within 50 years every man, woman and child in America will be overweight or obese."
In West Africa today, beauty pageants feature contestants who would be considered markedly obese in the US; many of the young women who represent the pinnacle of female beauty in these cultures weigh more than 90kg. In this regard, contemporary West Africa is quite similar to the US in the 1890s, when the 90kg actress Lillian Russell was considered the undisputed beauty of her time. Historically, far more cultures have mirrored contemporary West Africa and late-19th-century America than have resembled the US today, where an almost unprecedented ideal of thinness reigns supreme.
This is a culture whose need to control the world and the people in it is so intense that it has been driven to the preposterous conclusion that millions of unique individuals should all weigh within 5kg of an imaginary ideal weight. In fact, as we have seen, there is no valid medical reason why two women of the same height cannot weigh 45kg and 90kg respectively, while both maintain optimum cardiovascular and metabolic fitness, and excellent overall health. However, there are enormously powerful cultural, political and economic forces that ensure we do our best to make sure one of these women will remain miserable about her "disease".
If one were forced to come up with a six-word explanation for the otherwise inexplicable ferocity of America's war on fat, it would be this: Americans think being fat is disgusting. Fifty years ago, America was full of people whom the social elites could look upon with something approaching open disgust: blacks in particular, of course, but also other ethnic minorities, the poor, women, Jews, homosexuals, and so on. Nowadays, a new target is required.
As The Handbook of Obesity Studies notes, "In heterogeneous and affluent societies such as the United States, there is a strong inverse correlation of social class and obesity, particularly for females." In other words, on average, poor people in America are fat and rich people are thin. The disgust the thin upper classes feel for the fat lower classes has nothing to do with mortality statistics and everything to do with feelings of moral superiority. Precisely because Americans are so repressed about class issues, the disgust the (relatively) poor engender in the (relatively) rich must be projected onto some other distinguishing characteristic.
In 1853, an upper-class Englishman could be quite unselfconscious about the fact that the mere sight of the urban proletariat disgusted him. In 2003, any upper-class white American liberal would be horrified to imagine that the sight of, say, a lower-class Mexican-American woman going into a Wal-Mart might somehow elicit feelings of disgust in his otherwise properly sensitised soul. But the sight of a fat woman - make that an obese - better yet a morbidly [sic] obese woman going into Wal-Mart ... ah, that is something else again.
The single most noxious line of argument in the literature about obesity is that black
and Hispanic girls and women need to be "sensitised" to the "fact" that they have inappropriately positive feelings about their bodies. Readers may suspect this is a bad joke: I wish it were. One University of Arizona study found that, while only 10 per cent of the white teenage girls surveyed were happy with their bodies, 70 per cent of the black teenage girls were happy with theirs (the black girls weighed more, on average, than the white girls).
Obesity researchers and diet companies are doing their best to change this unacceptable situation. In recent years, diet companies in the US have targeted much of their advertising specifically towards upwardly mobile black and Hispanic women. As for obesity researchers, a recent article noted that black girls have better body images and lower rates of eating disorders than white girls, and also noted that they weighed more.
"These findings," the authors concluded, "should be used in the development of culturally sensitive public health intervention programs to help reduce the high rates of obesity within the black community and encourage black youth to achieve a healthy and reasonable [sic] body size." Here again, we see how crucial the health justification remains to all aspects of the war on fat.
How would a proposal for "culturally sensitive public health intervention programs" sound if it were translated (accurately) as a proposal to make black and Hispanic girls as neurotic about their weight as white girls tend to be, because these groups represent the best opportunity for expanding the market for the useless, expensive and dangerous products of the weight loss industry?
Thinness has a metaphorical significance today. Americans, Britons, Australians - and especially their elites - value thinness for precisely the same reason someone suffering from anorexia nervosa does: because not eating means not giving in to desire. Strangely, what these elites consider most desirable is a body whose appearance signals a triumph of the will over desire itself. Thus, bodily virtue is not so much indicated by thinness per se, but rather by an achieved thinness. Ultimately the war on fat is both a cause and a consequence of the transformation of the Protestant work ethic into the modern diet ethic.
The obesity myth thrives particularly in modern America because America is an eating-disordered culture. Moreover, the prime symptoms of this situation - increasing rates of excess weight, bulimia and anorexia - are also symptoms of, and have become metaphors for, a broader set of cultural anxieties.
Americans worry, with good reason, that they have become too big for their own good: that they consume too much, too quickly; that their cars, houses and shopping malls are too large; that their imperial ambitions to make the world safe for democracy and McDonald's are too grand. Under these circumstances, obsessing about the 5kg of extra weight that the average American adult has gained over the past 15 years has become a convenient way of avoiding a more direct engagement with any number of issues regarding America's excesses.
For upper-class Americans in particular, it's easier to deal with anxiety about excessive consumption by obsessing about weight, rather than by actually confronting far more serious threats to their social and political health. They may drive environmentally insane SUVs that dump untold tonnes of hydrocarbons into the atmosphere; they may consume a vastly disproportionate share of the world's diminishing natural resources; they may support a foreign policy that consists of throwing America's military weight around without regard to objections from its allies - but at least they don't eat that extra cookie when it's offered to them.
Edited extract from The Obesity Myth by Paul Campos, published by Viking, rrp $26.95. (copyright) Paul Campos 2004.
A big fat con
By: Paul Campos
Size really doesn't matter. You can be just as healthy if you're roly-poly as you can if you're slender, no matter what the fat police may say. Or so argues Paul Campos in this extract from his provocative new book, The Obesity Myth.
In January 2003, as America prepared to go to war with Iraq, the US surgeon general, Richard Carmona, warned the nation that it faced a far more dangerous threat than Saddam Hussein's supposed weapons of mass destruction. Rather than focusing on the danger posed by nuclear, biological and chemical weapons, Carmona told his audience, "Let's look at a threat that is very real, and already here: obesity."
Carmona is merely the latest in a series of surgeon generals who have treated America's expanding waistline as the nation's leading public health problem. In doing so, they have merely reflected the language of much of the medical establishment, which for decades has treated "overweight" and "obesity" as major health risks.
Fat is on trial, but until now the defence has been mostly absent from the court of public opinion. At bottom, the case against fat rests on the claim that the thinner you are, the longer you will live. Fat kills, we're told, and the prescription is clear: get thin.
The doctors and public health officials prosecuting the war on fat would have us believe that who is or isn't fat is a scientific question that can be answered by consulting something as crude as a body mass index chart (the BMI is a mathematical formula that puts people of different heights and weights on a single integrated scale). This, like so many other claims at the heart of the case against fat, is false. "Fat" is a cultural construct. According to the public health establishment's current BMI definitions, Brad Pitt, Michael Jordan and Mel Gibson are all "overweight", while Russell Crowe and George Clooney are both "obese". According to America's fat police, if your BMI is over 25, then you are overweight, full stop. Note also the radical difference between how our culture defines fashionable thinness for men and women. If Jennifer Aniston had the same BMI as her husband Brad Pitt, she would weigh approximately 25 kilograms more than she does.
According to the latest BMI figures, 64.5 per cent of American adults are either overweight (meaning they have a BMI of between 25 and 29.9) or obese (defined as a BMI of 30 or higher). (The latest Australian figures show 67 per cent of adult males and 52 per cent of adult women as either overweight or obese.) Studies have found an association between even mild amounts of excess weight and a significantly increased risk of premature death. For example, a highly publicised study published in The New England Journal of Medicine in 1995 found that women of average height who were as little as 12lb (5.4kg) overweight had a 60 per cent increased risk of mortality. A 1999 study published in The Journal of the American Medical Association (JAMA) estimated that excess weight led to about 300,000 premature deaths a year in America alone.
Meanwhile, the proportion of the population that maintains a dangerously high weight continues to climb: obesity in America has increased by more than 50 per cent over the past decade. If the authors of these studies are correct, America is facing a health crisis that, in the words of one anti-fat warrior, will make AIDS look "like a bad case of the flu".
The Centres for Disease Control warn that overweight and obesity put people at increased risk for congestive heart failure, coronary heart disease, diabetes, high blood pressure, obstructive sleep apnoea and other respiratory problems, and some cancers. The case against fat thus seems clear: having a BMI of 25 (this is a weight of 66kg for a woman of average height, and 81kg for a man of average height) or higher has been proven by medical science to cause myriad deadly conditions.
The question then becomes, what can we do about this epidemic that is putting in jeopardy the lives of the more than 135 million adult Americans who are currently overweight?
The solution to this crisis seems obvious: Americans (and those in other "fat" nations such as Britain and Australia) should find a way to weigh less. A recent article by Harvard Medical School researchers was more specific: "Adults should try to maintain a body mass index between 18.5 and 21.9 to minimise their risk of disease" (for a woman of average height, this would mean maintaining a weight between 49kg and 58kg).
How are we supposed to achieve these goals? Public health authorities assure us that the best path to healthy weight loss is a combination of caloric restriction - aka dieting - and exercise. Unfortunately, this classic prescription has an extremely high failure rate: the vast majority of dieters end up regaining all of the weight they lose, and many end up weighing more than they did prior to their attempts to lose weight. Given this record of failure, it's not surprising that the pharmaceutical industry has spent billions of dollars attempting to develop safe and effective weight-loss drugs. And for those whom neither dieting nor diet drugs can seem to help, weight-loss surgery is becoming an increasingly popular, if dangerous, option.
This, then, is the case against fat: the developed world, we are told, is on the verge of eating itself to death. The core belief of those prosecuting this case is that the BMI tables testify to a strong, predictable relationship between increasing weight and increasing mortality. That, after all, is what most people assume when they read that medical and public health authorities have determined a BMI of 25 or above is hazardous to a person's health. This belief, however, is not supported by the available evidence.
A 1996 project undertaken by scientists at the National Centre for Health Statistics and Cornell University analysed the data from dozens of previous studies, involving a total of more than 600,000 subjects with up to a 30-year follow-up. Among non-smoking white men, the lowest mortality rate was found among those with a BMI between 23 and 29, which means that a large majority of the men who lived longest were overweight according to government guidelines. The mortality rate for white men in the supposedly ideal range of 19 to 21 was the same as that for those in the 29 to 31 range (most of whom would be defined now as obese). In regard to non-smoking white women, the study's conclusions were even more striking: the BMI range correlating with the lowest mortality rate was extremely broad, from about 18 to 32, meaning a woman of average height could weigh anywhere within a 36kg range without seeing any statistically significant change in her risk of premature death.
In almost all large-scale epidemiological studies, little or no correlation between weight and health can be found for a large majority of the population - and indeed, what correlation does exist suggests that it is more dangerous to be just a little underweight than substantially overweight. So, let us look at the most cited studies for the proposition that overweight is a deadly epidemic in America today. Anyone who bothers to examine the evidence in the case against fat with a critical eye will be struck by the radical disconnection between the data in these studies and the conclusions their authors reach.
"Annual Deaths Attributable to Obesity in the United States", which appeared in JAMA in 1999, is the source for the endlessly repeated statistic that being overweight causes about 300,000 extra deaths in the US every year. (This "fact" has been cited in the major media more than 1700 times in the past two years alone.) Yet this survey reveals a very broad, U-shaped risk curve. For example, the study's data indicate that people with a BMI of 20 run the same risk of premature death as those with BMIs of 30, even though the former are ideally thin, while the latter are "obese". And both these groups have a slightly higher risk than people with a BMI of 25 ("overweight").
One would never guess from the authors' discussion of their findings, and the conclusions they reach, that their data showed little or no fluctuation in risk associated with differing body mass for the large majority of the people included in their study.
Furthermore, as Glenn Gaesser, a professor at the University of Virginia, points out, studies have consistently failed to find any correlation between increasing BMI and higher mortality in people 65 and over, and 78 per cent of the approximately 2.3 million annual deaths in the US occur among people who are at least 65. Thus, 78 per cent of all deaths lack even the beginning of a statistical link with BMI. "That leaves 500,000 annual deaths in persons under 65 that might be related to BMI," Gaesser told me. "These include deaths from every possible cause: motor vehicle and other accidents, homicides, suicides, cigarettes, alcohol, microbial agents, toxic agents, drug abuse, etc, etc. To think that 60 per cent [i.e., 300,000] of these deaths are due to body fat is absolutely preposterous."
"Overweight, Obesity and Mortality From Cancer", published in The New England Journal of Medicine in April 2003, was the subject of front-page stories in many of the US's leading newspapers. For example, a Los Angeles Times article reported that the study provided "the first definitive account of the relationship between obesity and cancer" and went on to quote the study's authors to the effect that perhaps as many as 90,000 deaths a year from cancer could be avoided if all adults maintained a BMI below 25 throughout their lives. The disjunction between this study's actual data and the alarmist headlines its authors helped generate is especially remarkable.
Among supposedly ideal weight individuals (BMI 18.5 to 24.9), the study observed a mortality rate from cancer of 4.5 deaths for every 1000 subjects. Among overweight individuals (BMI 25 to 29.9 - a category that in America currently includes about twice as many adults as the ideal weight cohort), the cancer mortality rate was 4.4 deaths for every 1000 subjects. In other words, overweight people actually had a lower overall cancer mortality rate than ideal weight individuals.
Most people, and indeed most doctors, simply assume that the heavier you are, the more likely it is you will suffer from coronary artery disease - hence the various cliches about artery-clogging fast food and the like. Yet several studies have specifically investigated the question of whether a high percentage of body fat correlates with the incidence of coronary artery disease. Answer: no, it does not. Even massively obese men and women do not appear to be more prone to vascular disease than average.
It is true that increasing weight is associated with high blood pressure and certain types of heart disease. But even here there is evidence that this correlation is not necessarily a product of being fat, but rather of losing and then regaining weight. Obese patients who have been put on very low-kilojoule diets subsequently display much higher rates of congestive heart failure than equally fat people who did not attempt to lose weight in the first place. The biggest evidentiary problem for those who insist there is a strong causal link between increasing weight and heart disease
is that deaths from heart disease have been plunging at precisely the same time that obesity rates have been skyrocketing.
Indictments in the case against fat invariably focus on diabetes, because Type 2 diabetes is much more common among heavier-than-average people. It has become routine to claim that Western society is about to be overwhelmed by a diabetes epidemic, that for the first time Type 2 diabetes is being seen among children, etc, and that the solution to this crisis is to make fat people thin. Actually, the definition of diabetes has changed (from a fasting blood sugar of 140 to a blood sugar of 126) and many more people have been diagnosed as suffering from the disease. Several recent studies indicate that the key to avoiding Type 2 diabetes is not to try to lose weight (indeed, there is much evidence that dieters are far more prone to the disease than average), but rather to make lifestyle changes in regard to activity levels and dietary content that greatly reduce the risk of contracting the disease, whether or not such changes lead to any weight loss.
Over the past three decades, according to Gaesser's survey of the literature, between 35 and 40 medical studies have found increasing body mass to be associated with a lower incidence of various cancers, and with lower mortality from cancer. Other diseases and syndromes that various medical studies indicate are less common among heavier people include emphysema, chronic obstructive pulmonary disease, hip fracture, vertebral fracture, tuberculosis, anaemia, peptic ulcer and chronic bronchitis, among others. Indeed, how many people are aware that heavier women have much lower rates of osteoporosis, which is a very common and serious condition among older women? Consider the potential implications for public health of the fact that hip fractures are 2 1/2 times less likely to occur among heavier women. Hip fracture is a leading cause of both death and permanent disability among older women (in Britain, more women die from osteoporosis-related hip fracture than from breast, cervical and uterine cancer combined).
There are some groups of heavier individuals - usually those with BMI figures in the mid-30s and above - who do suffer from worse health or shorter life expectancy than those of "ideal weight". Yet this does not of itself prove that such people's problems are caused by their excess weight. There are many other factors that disproportionately affect the heaviest people in our society, and that also correlate with poor health: most notably a sedentary lifestyle, poor diet, dieting-induced weight fluctuation, diet drug use, poverty, access to and discrimination in health care, and social discrimination generally. And yet all of the studies that are most often cited by anti-fat warriors almost completely fail to control for such factors.
The case against fat proceeds on the assumption that if a fat person becomes
thin, that person will acquire the health characteristics of people who were thin in the first place. Although this assumption may seem like simple commonsense, it is, like many commonsensical assumptions, quite dubious. If a person who is physiologically inclined to be fat loses weight, this does not transform that person into someone who is physiologically inclined to be thin.
To understand the implications of this distinction, consider that bald men die sooner, on average, than hirsute men, probably because bald men have higher levels of testosterone, which appears to lower life expectancy. Given this, surely no one would conclude that giving a bald man hair implants would improve his prospects for long life.
No one has ever successfully conducted a study into the health benefits of turning fat people into thin people, and for a very simple reason: no one knows how to turn fat people into thin people. This statement is in one sense shocking, despite the fact that there are few better established empirical propositions in the entire field of medicine. How can this be? After all, as those who prosecute the case against fat never cease to remind us, everyone knows how to lose weight: eat less and exercise more. In theory, this regimen should make people thin. In practice, it does not.
For example, in the US, more people than ever are dieting; percentages tripled over the course of the last generation. And the result? Americans weigh on average 15lb (nearly 7kg) more than they did 20 years ago. The vast majority of people who attempt to lose weight eventually gain back all the weight they lose, and sometimes more. So we simply don't know if people who lose a large amount of weight and keep it off permanently improve their health by doing so. This is what we do know: tens of millions of Americans are trying - more or less constantly - to lose 20 or 30lb (the average figure cited in surveys of dieters tends to be 25lb [11.3kg]). If you ask them why, most will tell you that they are doing so for the sake of their health, often on the advice of their doctors. Yet Gaesser notes that more than two dozen studies have found that weight loss of this magnitude leads to an increased risk of premature death, sometimes by an order of several hundred per cent.
Over the past 20 years, scientists have gathered a wealth of evidence indicating that cardiovascular and metabolic fitness, and the activity levels that promote such fitness, are far more important predictors of both overall health and mortality risk than weight.
The most extensive work in this area has been carried out by Steven Blair and his colleagues at Dallas's Cooper Institute, involving more than 70,000 people. What they have discovered is that, quite simply, when researchers take into account the activity levels and resulting fitness of the people being studied, body mass appears to have no relevance to health whatsoever. In Blair's studies, obese people who engage in at least moderate levels of physical activity have about one half the mortality rate of sedentary people who maintain supposedly ideal weight levels.
Similarly, a 1999 Cooper Institute study involving 22,000 men found the highest death rate among sedentary men with waist measurements under 34 inches (86cm), while the lowest death rate was found among fit men with waist measurements of 40 inches (102cm) or more. A 1995 Blair study found that improved fitness (i.e., going from "unfit" to "fit", with the latter requiring a level of exercise equivalent to going for a brisk half-hour walk four or five times a week) reduced subsequent mortality rates by 50 per cent. As Blair himself puts it, Americans have "a misdirected obsession with weight and weight loss. The focus is all wrong. It's fitness that is the key."
Why are we so afraid of the generally small health risks associated with above-average weight, while remaining comparatively indifferent to the much larger health risks associated with being a man, or poor, or black, or unusually thin?
Consider this: from the perspective of a profit-maximising medical and pharmaceutical industry, the ideal disease would be one that never killed those who suffered from it, that could not be treated effectively, and that doctors and their patients would nevertheless insist on treating anyway. Luckily for it, the health care industry has discovered (or rather invented) just such a disease.
It is called "obesity". Basically, obesity research is funded by the diet and drug industry - that is, the economic actors who have the most to gain from the conclusion that being fat is a disease that requires aggressive treatment. Many researchers have direct financial relationships with the companies whose products they are evaluating.
US government grant money is scarce, and the process for securing it extremely competitive. "When you apply for a grant," one prominent obesity researcher told me, "you have to make a strong case for funding by explaining the significance of the research." The researcher then asked me which of the following scenarios was most likely to produce a successful application:
1. "Though it is difficult to establish the independent contribution of obesity to morbidity and mortality, and it appears that lifestyle factors - such as poor diet and lack of physical activity - pose far greater health risks, we nevertheless request funding to study obesity as a matter of scientific curiosity, and also to assess whether it might be more prudent to get fat people fit rather than to get them thin."
Or: 2. "Obesity kills at least 300,000 Americans every year, and mathematical models of the obesity epidemic predict that within 50 years every man, woman and child in America will be overweight or obese."
In West Africa today, beauty pageants feature contestants who would be considered markedly obese in the US; many of the young women who represent the pinnacle of female beauty in these cultures weigh more than 90kg. In this regard, contemporary West Africa is quite similar to the US in the 1890s, when the 90kg actress Lillian Russell was considered the undisputed beauty of her time. Historically, far more cultures have mirrored contemporary West Africa and late-19th-century America than have resembled the US today, where an almost unprecedented ideal of thinness reigns supreme.
This is a culture whose need to control the world and the people in it is so intense that it has been driven to the preposterous conclusion that millions of unique individuals should all weigh within 5kg of an imaginary ideal weight. In fact, as we have seen, there is no valid medical reason why two women of the same height cannot weigh 45kg and 90kg respectively, while both maintain optimum cardiovascular and metabolic fitness, and excellent overall health. However, there are enormously powerful cultural, political and economic forces that ensure we do our best to make sure one of these women will remain miserable about her "disease".
If one were forced to come up with a six-word explanation for the otherwise inexplicable ferocity of America's war on fat, it would be this: Americans think being fat is disgusting. Fifty years ago, America was full of people whom the social elites could look upon with something approaching open disgust: blacks in particular, of course, but also other ethnic minorities, the poor, women, Jews, homosexuals, and so on. Nowadays, a new target is required.
As The Handbook of Obesity Studies notes, "In heterogeneous and affluent societies such as the United States, there is a strong inverse correlation of social class and obesity, particularly for females." In other words, on average, poor people in America are fat and rich people are thin. The disgust the thin upper classes feel for the fat lower classes has nothing to do with mortality statistics and everything to do with feelings of moral superiority. Precisely because Americans are so repressed about class issues, the disgust the (relatively) poor engender in the (relatively) rich must be projected onto some other distinguishing characteristic.
In 1853, an upper-class Englishman could be quite unselfconscious about the fact that the mere sight of the urban proletariat disgusted him. In 2003, any upper-class white American liberal would be horrified to imagine that the sight of, say, a lower-class Mexican-American woman going into a Wal-Mart might somehow elicit feelings of disgust in his otherwise properly sensitised soul. But the sight of a fat woman - make that an obese - better yet a morbidly [sic] obese woman going into Wal-Mart ... ah, that is something else again.
The single most noxious line of argument in the literature about obesity is that black
and Hispanic girls and women need to be "sensitised" to the "fact" that they have inappropriately positive feelings about their bodies. Readers may suspect this is a bad joke: I wish it were. One University of Arizona study found that, while only 10 per cent of the white teenage girls surveyed were happy with their bodies, 70 per cent of the black teenage girls were happy with theirs (the black girls weighed more, on average, than the white girls).
Obesity researchers and diet companies are doing their best to change this unacceptable situation. In recent years, diet companies in the US have targeted much of their advertising specifically towards upwardly mobile black and Hispanic women. As for obesity researchers, a recent article noted that black girls have better body images and lower rates of eating disorders than white girls, and also noted that they weighed more.
"These findings," the authors concluded, "should be used in the development of culturally sensitive public health intervention programs to help reduce the high rates of obesity within the black community and encourage black youth to achieve a healthy and reasonable [sic] body size." Here again, we see how crucial the health justification remains to all aspects of the war on fat.
How would a proposal for "culturally sensitive public health intervention programs" sound if it were translated (accurately) as a proposal to make black and Hispanic girls as neurotic about their weight as white girls tend to be, because these groups represent the best opportunity for expanding the market for the useless, expensive and dangerous products of the weight loss industry?
Thinness has a metaphorical significance today. Americans, Britons, Australians - and especially their elites - value thinness for precisely the same reason someone suffering from anorexia nervosa does: because not eating means not giving in to desire. Strangely, what these elites consider most desirable is a body whose appearance signals a triumph of the will over desire itself. Thus, bodily virtue is not so much indicated by thinness per se, but rather by an achieved thinness. Ultimately the war on fat is both a cause and a consequence of the transformation of the Protestant work ethic into the modern diet ethic.
The obesity myth thrives particularly in modern America because America is an eating-disordered culture. Moreover, the prime symptoms of this situation - increasing rates of excess weight, bulimia and anorexia - are also symptoms of, and have become metaphors for, a broader set of cultural anxieties.
Americans worry, with good reason, that they have become too big for their own good: that they consume too much, too quickly; that their cars, houses and shopping malls are too large; that their imperial ambitions to make the world safe for democracy and McDonald's are too grand. Under these circumstances, obsessing about the 5kg of extra weight that the average American adult has gained over the past 15 years has become a convenient way of avoiding a more direct engagement with any number of issues regarding America's excesses.
For upper-class Americans in particular, it's easier to deal with anxiety about excessive consumption by obsessing about weight, rather than by actually confronting far more serious threats to their social and political health. They may drive environmentally insane SUVs that dump untold tonnes of hydrocarbons into the atmosphere; they may consume a vastly disproportionate share of the world's diminishing natural resources; they may support a foreign policy that consists of throwing America's military weight around without regard to objections from its allies - but at least they don't eat that extra cookie when it's offered to them.
Edited extract from The Obesity Myth by Paul Campos, published by Viking, rrp $26.95. (copyright) Paul Campos 2004.
