Jan. 29 (HealthDay News) -- Stomach banding, commonly called lap band surgery, is a safe and effective method of helping obese adolescents lose weight, U.S. researchers report.

In lap band surgery, an inflatable silicon ring is placed around the upper portion of the stomach. This creates a smaller stomach, which makes people feel full sooner and reduces the amount they eat. In the United States, lap band surgery is currently only approved for adults.

This study of 53 morbidly obese patients, ages 13 to 17, found that the teens lost an average of 50 percent of their weight a year after their surgery. Morbidly obese people have a body mass index (BMI) of 40 or above and are usually about 100 pounds overweight.

According to researchers at New York University School of Medicine, none of the patients had complications requiring readmission to the hospital. Two patients did experience slippage of the bands, two developed hiatal hernias, and one patient had a wound infection. All these conditions were treated by outpatient procedures.

A few patients experienced mild hair loss and iron deficiency. They were treated with nutritional counseling and vitamin supplementation.

The study, published in the January issue of the Journal of Pediatric Surgery, is the first to evaluate lap band surgery in patients this young, the authors said. All of the study participants (mostly girls) had a history of obesity for at least five years, and many had conditions found in obese adults, such as diabetes, high blood pressure and sleep apnea. The participants had made previous unsuccessful attempts to lose weight, using diet and exercise regimens.

"This study suggests that the lap band provides a safer and equally effective weight loss strategy compared to the gastric bypass," study lead author Dr. Evan Nadler, director of pediatric minimally invasive surgery and assistant professor of surgery, said in a prepared statement.

In gastric bypass surgery, the stomach is divided and reshaped into a small pouch, which is connected directly to the middle portion of the small intestine. Side effects of gastric bypass included intestinal leakage and bleeding, blockage of the intestines, and severe nutritional deficiency, Nadler noted.