There are no magic solutions for fat children, but there are programs that can help.

At the University of Pittsburgh School of Medicine, psychologist Leonard Epstein and his colleagues have been helping obese children slim down for a decade. Known as the Stoplight Diet for Children, the program is sponsored by the National Institute of Child Health and Human Development.

On the Stoplight Diet, children and their families learn how to gradually change their eating and exercise habits over a minimum of eight weeks. Instead of simply counting calories, they learn how to classify foods according to three signals on a traffic light. High calorie foods are classified as red; moderate-calorie foods are yellow; and low-calorie foods are green.

The program also stresses daily weigh-ins; regular exercise and minimizing TV watching and other sedentary activities. The goal is to lose weight slowly -- about half a pound to a pound per week. Five years after being on the Stoplight Diet, about a third of the youngsters still maintain ideal weight for their height, age and sex.

At Georgetown University Hospital, the Department of Pediatrics treats overweight and obese children at a special clinic for eating disorders. "We help children increase the nutritional quality of what they are eating," says Dr. Dorothy Richmond, a pediatrician at the clinic.

A major goal of the Georgetown clinic is to increase physical activity and help overweight children burn more calories. "We try to get them away from being couch potatoes," says Richmond.

Children who enter the Georgetown program undergo an initial evaluation that includes psychological and medical testing. Then they return once a week for weigh-ins. Every other week, they receive additional instruction about eating and exercise.

Most children lose about half a pound to a pound per week, but for the very young -- those 2 to 3 years old -- the goal is simply to help them not gain any more weight until they can grow taller.

"We try to work with the whole family," says Richmond.

Resources: Georgetown University Medical Center, Dept. of Pediatrics, 3800 Reservoir Rd. NW, Washington, D.C. 20007. Phone: 687-KIDS. Cost: Initial evaluation is $200; thereafter, $26 every other week.

"The Stoplight Diet for Children," by Leonard Epstein and Sally Squires (Little, Brown and Co., 1988).