When Joan went home for Thanksgiving last month, she joined in the spirit of the holiday and ate until her skirt was far too snug for comfort and her body was crying out for an afternoon nap. Unlike the rest of her family, however, after consuming a heaping plate of turkey, stuffing, gravy, sweet potatoes, green beans, and hefty chunks of pecan pie and pumpkin pie topped with vanilla ice cream, Joan did not stop.

While she tidied up the kitchen for her family, Joan polished off another plate of turkey swimming in gravy, a pan of stuffing, an entire pecan pie, a gallon of ice cream, and a gallon of milk. Then, cursing her bloated body and lack of will-power, Joan locked herself in the bathroom and vomited up every last bite of her meal.

Joan (not her real name) is a Harvard senior afflicted with a disease that is now epidemic among college students across the country--bulimia. Primarily found among achievement-oriented, obsessive, perfectionist females ranging in age from eight to 50, bulimia--Greek for "ox hunger"--is a disorder that psychiatrists and medical authorities are only beginning to understand; the American Psychiatric Association officially recognized bulimia (or bulimarexia, as it is also known) as a disease just last year.

Unlike anorexia nervosa, whose sufferers think constantly about food yet deny them-selves nourishment while exercising their bodies into a state of abnormal emaciation, bulimia often afflicts women who appear healthy, radiant and at an ideal weight. Despite their differing approaches to weight loss, however, bulimics and anorectics are alike in a number of ways. Their inflated fear of fatness, distortion of true 'body image, and extremely low self-esteem lead them to manipulate their metabolisms and turn an innate self-disgust into a dangerous attack on their own bodies.

LAST SUMMER the employees of the office where Susan worked asked her to get them frozen yogurt when she went on an errand. Knowing that frozen yogurt was her particular dieting downfall, Susan resolved not to have any, until she got to the store and discovered that three of her favorite flavors were in stock.

Suddenly feeling out of control of her eating, Susan ordered a large mixture of the flavors and ate it all, and then went into another yogurt store where she ordered another large frozen concoction and wolfed it down, barely tasting or enjoying the food.

With a mixture of nausea and panic at the number of calories she had just consumed, Susan drove quickly back to her office where she delivered the yogurt to her co-workers, and then went into the bathroom where she made herself throw up.

Susan--a pretty, slender Harvard sophomore--is still plagued with occasional bouts of bulimia, although now she feels more in control of the problem than she ever has in the five years she has been afflicted with it. Like most sufferers of bulimia, Susan has made several attempts to stop gorging/purging--usually after a frightening or disappointing experience with vomiting.

For example, Susan says, "At one point in high school, I was vomiting three or four times a day and I had a big red welt on the back of my hand where my teeth scraped when I put my fingers down my throat. It was then that I started throwing up blood and I got scared about what I was doing to myself."

Susan wasn't scared enough to stop, however, and the destructive behavior continued, although it did not always rid her of her food binge calories. "I vividly remember lying in a heap on my bathroom floor, crying because I just couldn't throw up the five bagels I had eaten," she recalls.

Like the vast majority of sufferers, Susan feels an intense pressure to be thin, smart, career-oriented and successful, and often this pressure has led her to turn to food for comfort. "Being at Harvard just makes the problem worse because everyone is out to succeed here, and people move so fast that they often don't take the time to be friendly or personable. When you feel like the university and the people are impersonal and all there is to do is study and sit around inside, then it is extremely easy to overeat," she says.

Sally, a Harvard freshman who occasionally gulps handfuls of laxatives to cleanse her body of excess calories consumed during food binges, agrees. "I think Harvard is a perfect microcosm for eating disorders," she says. Afflicted with one offshoot of bulimia, Sally shuns forced vomiting ("I hate the idea of hurting myself"), and instead relies on laxative overdoses to combat overeating.

Like many victims of bulimia. Sally learned about laxative abuse through friends who used them, diuretics and diet pills to lose or maintain weight. "I saw laxatives as a way to lose weight easily and painlessly," Sally says. "On days when I took laxatives, I ate whatever I wanted in huge quantities--whatever looked good, and whatever fattening combination of foods I wanted, I would eat."

Like all sufferers of eating disorders, Sally also spends a lot of time thinking about food, and whether she will be able to eat a normal meal without feeling compelled to purge her body immediately afterwards. "There are some mornings when I am lying in bed and I just don't want to get up because I know my eating will be out of control," she says regretfully. "I'll concede defeat at eight O'clock in the morning and think, 'I am a failure for today.'"

JILL CARNI, a recovered anorectic who is a counselor for eating disorders in Cambridge as well as a consultant to various institutions, colleges and mental health facilities, sees a number of Harvard undergraduates, graduate students, and even Harvard employees in her practice. "At Harvard there is a lot of pressure to achieve socially, academically and careere-wise, and for many people food can become the anaesthetic that dulls their mind from the constant grind," she says. Marlene Boskind-White, a New York psychotherapist who deals with eating disorders, places much of the blame for the problem on the high standards the modern women feels she must live up to. "We have to be thin, beautiful, in good health; and on top of that, we have to have career success and be responsible for the children," she says.