About 20 to 30 minutes after a meal, the patient opens the valve and for the next 10 minutes drains about 30 percent of the calories consumed right into the toilet. In the trial study, people using this device lost an average of 12.1 percent of their body weight after a year. “Patients need to be regularly monitored by their health-care provider and should follow a lifestyle program to help them develop healthier eating habits and reduce their calorie intake,” Dr. William Maisel, deputy director for science and chief scientist at the FDA’s Center for Devices and Radiological Health said. Dr. Shelby Sullivan of Washington University in St. Louis, who helped test the AspireAssist and several other medical devices, says it’s a good option for the extremely obese patients. The latest data from the Centers for Disease Control and Prevention shows that 38 percent of U.S. adults are obese.