n implantable device that uses electrical signals to block the vagus nerve, which helps regulate digestion, has shown early success in clinical trials. The experimental therapy, developed by Enteromedics, a medical-device company based in St. Paul, MN, is part of a growing trend to develop alternatives to gastric bypass surgery, an often highly successful but invasive procedure to curb obesity.

"We need an approach to this that is safer than current alternatives and efficient to perform," says Christopher Thompson, a surgeon at Brigham and Women's Hospital who tests new surgical tools and methods.

As the obesity epidemic booms, so has the number of people undergoing gastric bypass surgery, a procedure in which the stomach is surgically reduced to about the size of a lemon. The American Society for Metabolic and Bariatric Surgery estimates that gastric bypass rates have doubled in the United States in the past five years, from about 100,000 in 2003 to approximately 200,000 in 2007.  Read More...