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By Elissa Elliott


Fat!

The science of obesity.

My husband and I have an airline mantra that we strictly adhere to: "Don't give up the armrest." Which means: when the person sitting next to you asks if he or she might please raise the armrest, our response is a courteous but firm "no." Why? Because most often the person asking is obese and cannot squeeze his plump derrière into the space allotted by the airlines. My husband and I reason that we paid for a full seat, and in the past, we've experienced the uncomfortable effect of someone else's spillage causing us to sit knock-elbowed the entire flight. And to be embarrassingly truthful, such encounters often lead to disgusted dialogue once we're safely out of the plane: "How can he live that way? Does he know how he looks? What a lack of self-control!" Paul Campos, the author of The Obesity Myth: Why America's Obsession with Weight is Hazardous to Your Health, would like to strangle us. Americans have created a false and unfounded hysteria about fat in general, Campos argues, and obese people are one more segment of the population that we have ostracized unfairly. They cannot help who they are. They are programmed to fluctuate around a predetermined genetic weight. And the rest of us who are frantically attempting to look like the slim, sleek magazine models are dieting ourselves to death—literally. Campos identifies study after study in which, he alleges, researchers have erroneously misrepresented and manipulated their data to pinpoint fat as the culprit. Why? Oftentimes, the studies are funded by the very organizations—diet and weight-loss programs—that want us to become obsessed with losing weight.

In medical terms, whether or not a person is obese is determined by the body mass index, or BMI, a measurement of body fat based on height and weight. (To check your own BMI, go to www.nhlbi.nih.gov.) Today, more than 60 percent of Americans are either overweight (BMI >25), obese (BMI >30), or morbidly obese (BMI >40). Generally speaking, a BMI of 19 to 25 indicates a healthy weight.

A particularly compelling study done in 1996 by the National Center for Health Statistics and Cornell University analyzed dozens of previous studies to investigate whether or not the relationship between body weight and mortality was meaningful. The results were startling:

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 currently as "obese"). The researchers were sufficiently struck by this to point out that since their analysis of existing studies had found "increased mortality at moderately low BMI for white men comparable to that found at extreme overweight, which does not appear to be due to smoking or existing disease," it followed that "attention to the health risks of underweight is needed, and body weight recommendations for optimum longevity need to be considered in light of these risks."1

Even more astounding was what they found for women. The authors concluded that, for non-smoking, white women, the BMI range correlating with the lowest mortality rate was extremely broad, from around 18 to 32, meaning a woman of average height could weigh anywhere within an 80-pound range without seeing any statistically significant change in her risk of premature death.2

Like Campos, Dr. Jeffrey Friedman, a researcher at the Howard Hughes Medical Institute and the Rockefeller University and the scientist who led the team that discovered the obesity hormone leptin in 1995, believes the obese get a bad rap. He says, "People often reserve their harshest judgments for those conditions about which the least is known."3 Friedman believes obesity is not a personal failing; typically it is a result of genetic factors beyond our control.

True, says Dr. Katherine Flegal of the National Center for Health Statistics. The general population has gained 7 to 10 pounds over the past 20 years, but the much larger increase at the upper end of the bell curve—an average increase has been of 25 to 35 pounds among the obese.4

Friedman begs us to take a closer look at our body mechanics—systems that are not yet fully understood. Hormones are responsible for balancing our caloric intake and energy expenditure (the amount of calories we burn off) within a 10- to 20-pound range. For example, one hormone produced by fat tissue, leptin, helps maintain body weight, but if there are mutations (or mix-ups) in the gene that codes for leptin, a decrease in metabolism or increased appetite can result. And this in turn leads to obesity.5

Because our weight is not primarily subject to volition, Friedman argues, over the long term dieting generally fails. We are going against our body's inner drives. Campos agrees and goes one step further. Not only is it extremely hard to lose weight, it's positively dangerous in many cases to lose a substantial amount of weight. He cites two leading dissenters in obesity research, Paul Ernsberger and Paul Haskew: "the astronomical death rate of crash dieters that regain their lost weight [as in fact almost all do] suggests that the hazards associated with fatness may be mainly related to rapid weight loss and regain of weight, not to obesity itself."6

If you think back to your introductory physics class and the first law of thermodynamics, which states that all energy within a closed system must stay constant, then you'll understand that in order for our weight to stay constant, our calorie intake must equal our energy expenditure.:

The implications of this simple equation are frequently underappreciated in discussions about the causes of obesity. Body weight is remarkably stable in humans. The average person consumes one million or more calories per year, yet weight changes very little in most people. These facts lead to the conclusion that energy balance is regulated with a precision of greater than 99.5 percent, which far exceeds what can be consciously monitored.7

To tabulate our calorie intake is quite easy. But energy expenditure is vastly variable. In a 1999 study published in Science, 16 subjects were overfed 1,000 calories per day for six weeks. Scientists measured each subject's non-exercise activity thermogenesis (NEAT), a baseline measurement of how much energy one needs to perform all the routine activities of daily life, including fidgeting and involuntary movements. What the scientists found astonished them. The change in the subjects' NEAT value varied anywhere from 0 to 692 calories (the latter being equivalent to running 6.2 miles).8 In short, weight is far less a matter of personal control than has been supposed.

"Come on," we say. "Are you blind? Can't you see all the fat people? But Friedman responds, "Are we going to put our faith in anecdotal experiences or real numbers?"9 Think Jane Russell and Marilyn Monroe. Think ample Miss Americas of the 1950s. And what about the furor caused by Twiggy's waif look in the 1960s? Times have changed; the coffee-Altoids-cigarette look is all the rage.

Alas, even if we buy into this notion of fat being genetic—even if we boycott dieting and instead focus on our exercise because now we know we can be fit and fat—this would have little effect on the social stigmas that go along with being overweight. We want the unattainable bodies of the airbrushed and corseted.

It seems we have created a monster. Ludwik Fleck, in his Genesis and Development of a Scientific Fact, argues that "once a structurally complete and closed system of opinions consisting of many details and relations has been formed, it offers enduring resistance to anything that contradicts it."10 Can you imagine what would need to happen for us to fundamentally change our attitude to obesity?

But I have only nudged the sleeping dragon. Granting that Campos, Friedman, and other mavericks are right about the genetic basis for obesity, there are still many questions to answer. Why are there more poor fat people than rich fat people? Why is there an alarming increase in child obesity? Why are corporations signing multimillion dollar contracts with schools to put their fatty foods in kids' sweaty hands? (For a scathing account of how we've lost control of our eating habits, read Greg Critser's book, Fat Land: How Americans Became the Fattest People in the World.) We are, without question, an eating-disordered culture, quite apart from genetic predispositions.

As for our in-flight mantra, my husband and I still maintain the armrest rule. It's just more comfortable. But we've begun mentally placing ourselves in our fat neighbor's shoes and giving him a little respect.

Elissa Elliott is a writer living in Rochester, Minnesota.

1. Paul Campos, The Obesity Myth: Why America's Obsession with Weight Is Hazardous to Your Health (Gotham Books, 2004), p. 11.

2. Campos, p. 12.

3. Dr. Jeffrey Friedman, "Modern Science versus the Stigma of Obesity," Nature Medicine 10 (June 1, 2004): 563-69.

4. Dr. Katherine M. Flegal, "Trends in Body Weight and Overweight in the U. S. Population," Nutrition Reviews 54 (April 1996): S97-S100.

5. Friedman, p. 563.

6. Campos, p. 220.

7. Friedman, p. 567.

8. Campos, p. 177.

9. Dr. Jeffrey Friedman, personal communication, June 2004.

10. Ludwik Fleck, Genesis and Development of a Scientific Fact (Univ. of Chicago Press, 1979), p. 27.


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