If all goes according to plan, we will have another nonsurgical option close behind: the EndoBarrier. This is a gastrointestinal liner that doctors insert through the patient's mouth and past the stomach so that it covers the first two feet of the small intestine. The theory is that when food has less contact with the digestive tract, your metabolism speeds up. Initial clinical studies bear this out: Average excess weight loss on the device is about 20 percent after three months, 30 after six. Patients are currently being studied to 12 months, and early results suggest they may lose as much as 40 percent of their excess weight. And within one week of getting the EndoBarrier—before any weight loss occurred—patients with type 2 diabetes went into remission (the same thing happens after the far more invasive gastric bypass surgery). Researchers believe our hormonal regulation of blood sugar changes when food skips the first part of the intestinal tract, causing diabetes to go into remission. "There's no doubt that the presence of something inside your digestive system is signaling your brain," says Nadey Hakim, MD, a British bariatric surgeon studying the temporary insertion of a fluid-filled balloon to reduce stomach volume and trigger weight loss. "It's beyond a feeling of fullness; hormonal changes really happen."
Scientists have been puzzling over the gut's mysterious interaction with the brain for decades. In the early 1980s, researchers experimented with an ulcer treatment that involved cutting the vagus nerve—it connects the gut with the brain and conveys hunger messages. The doctors found that their patients suddenly started losing weight. But as an ulcer treatment the surgery didn't pan out, and the weight loss findings weren't pursued.