Around a dozen years ago, researchers noticed that some patients with chronic conditions such as heart disease fared better than others. This should have been encouraging news, perhaps a clue to future treatments. Instead, researchers were baffled. Because the factor that seemed to be protecting these patients was fat: They were all overweight or mildly obese.
“When health-care professionals get their first nutrition books, there’s a chapter on obesity,” says Glenn Gaesser, director of the Healthy Lifestyles Research Center at Arizona State University. “And it generally says that fat people are unhealthy and thin people are healthy.”
Researchers immediately began trying to explain this “obesity paradox”—or, more often, to explain it away. Carl Lavie, a cardiologist in Jefferson, Louisiana, was one of the first clinicians to describe the paradox. It took him over a year to find a journal that would publish his findings. “People thought, ‘This can’t be true. There’s got to be something wrong with their data’,” he told Quartz.
“People thought, ‘This can’t be true. There’s got to be something wrong with their data.’”
Since then, dozens of studies have confirmed the existence of the paradox. Being overweight is now believed to help protect patients with an increasingly long list of medical problems, including pneumonia, burns, stroke, cancer, hypertension, and heart disease. Researchers who have tried to show that the paradox is based on faulty data or reasoning have largely come up short. And while scientists do not yet agree on what the paradox means for health, most accept the evidence behind it. “It’s been shown consistently enough in different disease states,” says Gregg Fonarow, a cardiology researcher at the University of California, Los Angeles.
The researcher who did most to kick off the debate, and in the process became the object of much of the pushback it generated, is an epidemiologist at the US Centers for Disease Control and Prevention named Katherine Flegal. Read more