At a White House news conference in December 1994, then-US surgeon general C. Everett Koop announced a national weight-loss program, claiming that obesity had become the country’s second-leading cause of mortality, “resulting in roughly 300,000 lives lost each year.”
This was the start of the statistic’s long and illustrious career. The number was cited by pundits and experts alike to emphasize the intensity of the “obesity pandemic.” It was used in hearings before the Food and Drug Administration for weight-loss drugs with uncertain safety profiles. One medicine, dexfenfluramine (Redux), was eventually taken off the market due to heart valve damage in patients. Another, sibutramine (Meridia), was taken off the market because it was linked to an increased risk of heart attacks and strokes.
After a decade, the number had risen to about 400,000 fatalities due to obesity, with forecasts that it would soon exceed half a million—roughly 20% of all annual deaths in the United States. However, by 2005, these seemingly insurmountable figures had been reversed. Katherine Flegal, a senior scientist at the Centers for Disease Control and Prevention at the time and today one of the most referenced epidemiologists in her profession, was the statistic killer.
Flegal led a study to better understand the relationship between body size and mortality, which revealed something many scientists—and definitely the general public—did not expect: the yearly death toll from obesity was just over 100,000. Even more intriguing, persons who were classified as clinically “overweight” lived longer than those who were classified as “normal” weight. (So, when the overweight and obese categories were combined together, the total was under 26,000 fatalities, as in prior research.)
Her work shouldn’t have made such a sensation in the first place. It was backed by the CDC and supported by additional studies (it even got a Charles C. Shepard Science Award in 2006, one of the agency’s highest distinctions). Despite this, the study was welcomed with a barrage of skepticism and criticism.
“People were calling journalists ahead of time, saying our article was garbage,” Flegal explains. “Our findings sparked debate because someone was looking for a fight.”
Retro Report teams up with Scientific American in this short documentary to look at how body size biases can influence the questions scientists research and the information people believe to be accurate.In the disputed field of obesity research, myths, misconceptions, and biases are pervasive and extensively documented. They are bolstered, according to Flegal, by societal weight stigma and the pharmaceutical and weight-loss businesses’ financial interests. She continues, “The entire subject of body weight and obesity has become extremely difficult to investigate scientifically.” “There’s a lot of emotion involved, and a lot of different interests.”
The famed “300,000 fatalities” statistic, despite the absence of supporting facts, nonetheless lives on today as an example of the perseverance of engrained attitudes regarding obesity. It has appeared in opinion pieces in the Hill, the Washington Post, and a number of local publications in the last year. (Most have used the Health Statistics Center of the West Virginia Department of Health, which hasn’t been updated since 2003.) It’s been mentioned in prominent medical journals, health guides, and even a congressional bill recently. It’s also a popular choice among weight-loss clinics across the country.
Flegal believes that “people are just more comfortable with a greater number—they prefer it to be larger.” “I don’t believe discomfort should be considered a factor in science, but I believe it has a larger impact than we understand.”
Bias muddles the scientific process. In nutrition science and medicine, this bias typically translates to the belief that being thinner is better, and that being skinnier is healthier. When the facts appear to contradict that preexisting concept, the phrase “obesity paradox” is frequently used to describe the situation.
“You can disclose the same obesity findings 100 times and it will always be termed ‘unexpected,” adds Flegal. “At what point would you change your view and say this may be the expected outcome?”
This so-called paradox has been observed in a variety of diseases, including heart disease, lung cancer, type 2 diabetes, and stroke, to name a few. According to Bette Caan, a cancer researcher at Kaiser Permanente who discovered her own “paradox” in breast cancer, the name “obesity paradox” can often lead to skepticism about such findings, even when they present an opportunity to learn something new.
“It’s human nature for people to look for proof to back up their beliefs,” Caan explains. “We must investigate where the data leads us.” Her own “unexpected findings” led to a breakthrough that could have far-reaching implications for breast cancer patients across the country: preserving muscle during therapy is considerably more crucial than avoiding weight gain for survival.
“We can’t remain stuck in what we’ve got.”