Some people get most calories at night

When Carlo Porreca's three children were babies, he frequently got up at night to check on them. Years later, when they were teens, he was still getting up at night, but by then he was going to the kitchen to eat.

At first he nibbled on a few crackers, but then he began gobbling cookies and sandwiches.

For more than 20 years, he ate three or four times between midnight and 4 a.m. "It took on a life of its own, and my body started waking me up for the food," says Porreca, now 62, a computer manager in Philadelphia. One night he even cooked a steak.

He put on 50 pounds before he was diagnosed with a disorder called night eating syndrome.

Like Porreca, people who have this condition consume a third or more of their daily calories after dinner, either before going to bed or during the night, says psychologist Kelly Allison of the Weight and Eating Disorders Program at the University of Pennsylvania School of Medicine in Philadelphia. They aren't sleepwalking; they're aware of what they're doing. "But there is a feeling of compulsion and anxiety associated with it."

She and her colleagues at the university have found that the antidepressant Zoloft is effective in controlling night eating, and Allison also has explored treating it with behavior modification strategies.

Allison has written a new book, "Overcoming Night Eating Syndrome," with Sara Thier and Albert Stunkard. Stunkard is the University of Pennsylvania psychiatrist who discovered the syndrome in the early 1950s.

Estimates vary on how many people have this problem, but research suggests that it affects 6 percent to 8 percent of people treated in obesity clinics and about 1.5 percent of the general population, Stunkard says.

People of normal weight sometimes are affected, too, and it may be a pathway to the development of obesity, he says.

Daytime eating is light

Penn researchers have studied more than 100 patients with the condition and also have gathered data from more than 2,000 others who've visited their Web site at www.uphs.upenn.edu/weight.

Night eaters are different from those who rise occasionally to snack or who eat a lot of food several times a week before bed.

Stunkard says night eaters often eat sparingly early in the day. "The disorder represents a shift of the biological rhythm of eating to later in the day," he says.

People with the syndrome may, for example, eat 700 to 800 of their 2,200 daily calories at night. They may eat peanut butter out of a jar or chocolate cake or leftovers from dinner, Allison says.

The emotional and physical impact is circular. "The eating helps soothe people and makes them feel better for a short time, but it also increases their weight, which makes them feel worse," she says.