While our culture offers infinitely more temptations than the prehistoric world of our ancestors (they didn't watch commercials for hamburgers at 9 P.M.), what about the environment in our minds? Any number of forces conspire to lure us to the fridge: stress, boredom, celebration, misery, and that old standby "It's time to eat." Whether it's our psychological state or our hardwired nature that predominates is the question that most divides biologists and behaviorists, with the former saying that most of our eating habits are preordained and the latter believing that much about hunger can be taught, controlled, or unlearned.
Susan Head, PhD, a clinical and health psychologist in private practice in Durham, North Carolina, helps patients with the emotional side of obesity and dieting, as she previously did at the Duke Diet & Fitness Center. Head identifies two misuses of hunger, both of which lead to overeating. One has to do with that enticing exterior environment, where portions have expanded and food is everywhere. "A lot of people are eating unconsciously these days," Head says. "They don't wait till they're hungry. They're eating like robots. The doughnuts are there—say, at a meeting—and people eat them." For them, eating is about availability, appetite (desiring food), and scheduling ("Lunchtime!"). Hunger has nothing to do with it.
The other kind of overeater has absorbed the ambient cultural anxiety about weight and enjoys the feeling of being hungry (or at least of being "not full") because, Head says, "being not full means I'm losing weight—hunger is good." So she puts off eating through the early stages of hunger—which include having thoughts about food and a vague empty feeling—until she reaches the growling- or aching-stomach stage, at which point she could eat a horse, and often does (or the equivalent in pizza).
Taken to the extreme, such hunger denial is expressed as anorexia, which is an example of the power of the mind, or will, over the demands of the body. Anorexics, Head says, don't even admit they're hungry; they define that starving feeling as "success." Their eating experience is so dominated by rules, and has so little to do with what their bodies are telling them, that they have redefined all the terms to express it. "Anorexics are way too insensitive to hunger and way too sensitive to fullness," Head explains. "Any absence of hunger is 'full'"—and while full feels comforting and soothing to most people, it feels terrifying to the anorexic.
Head believes that all of these habits—unconscious eating, hunger denial followed by overeating, and eating disorders like anorexia—can be broken. Both overeaters and undereaters are trying to ignore what's actually an essential internal meter for good eating. Head works with tried-and-true tools to get the hunger apparatus working again. Patients use hunger scales to rate their hunger and fullness from 1 to 10, relearning what hunger feels like and when to respond to it. They also learn to redefine fullness or satisfaction so that it doesn't mean "stuffed."
Some people can go a good part of the day without food; others become ravenous without regular feeding. Some are full after half a cheeseburger; others finish one and want a few more. Are such differences all in our heads?
Our minds and bodies are so linked that sometimes what seems psychological is almost completely biological or chemical in nature. This became clear long ago in regard to hunger, when an American researcher during World War II put a group of volunteers on a semistarvation diet to study how to help victims of wartime famine. As the men lost an average of 25 percent of their body weight, they became not only sluggish and cold (signs of a slowed metabolism) but also obsessed: They were constantly hungry, they talked and thought and daydreamed about food, they read cookbooks and fantasized about meals, they carefully guarded their rations from others, they became increasingly irritable with one another.
Eating-disorder experts have come to recognize, in light of this study and others, that some psychological symptoms of anorexia nervosa—obsessing about food, hoarding it—occur as a biological response to deprivation. Rather than stemming from some neurotic fixation, these symptoms appear because the body is screaming "Eat!"—as it does whenever a person's weight has dropped below the set point.