Today, researchers are digging into what drives weight gain, and some are beginning to suggest that we have been confusing cause and effect.
What if it’s not overeating that causes us to get fat, but the process of getting fatter that causes us to overeat?”
Recently The Journal of the American Medical Association (JAMA) published a provocative piece that asked precisely that question. Shortly before publishing in JAMA, the authors, summed up their argument in a New York Times Op-Ed: “Always Hungry? Here’s Why.”
There, David Ludwig, a professor of pediatrics at Harvard Medical School and director the New Balance Foundation Obesity Prevention Center at Boston Children’s Hospital, and Mark Friedman, vice president of research at the Nutrition Science Initiative did a superb job of distilling their argument into terms a layman can understand.
They suggest that chronic overeating represents a symptom rather than the primary cause of piling on the pounds. Indeed, Ludwig and Friedman argue, dieting itself may induce changes in our metabolism that leads us to regain weight when we begin to lose it.
They explain their theory: When we eat hearty meals, “we lock . . . more calories away in fat tissue.” As a result, “fewer are circulating in the bloodstream to satisfy the body’s requirements.” In other words, there are not enough calories in our bloodstream to give us the energy to do what we want to do.
“If we look at it this way,” they continue, “it’s a distribution problem: We have an abundance of calories, but they’re in the wrong place. As a result, the body needs to increase its intake. We get hungrier because we’re getting fatter.”
Ludwig and Friedman compare the process to what happens when patients suffer from “edema, a common medical condition in which fluid leaks from blood vessels into surrounding tissues. No matter how much water they drink, people with edema may experience unquenchable thirst because the fluid doesn’t stay in the blood, where it’s needed.
“Similarly,” they suggest, “when fat cells suck up too much fuel, calories from food promote the growth of fat tissue instead of serving the energy needs of the body, provoking overeating in all but the most disciplined individuals.”