How Weight-Loss Surgery Improves Diabetes Control
Key hormones, amino acids altered during digestion, study finds
TUESDAY, April 30, 2013 (HealthDay News) -- Gastric bypass -- a widely used weight-loss procedure -- appears to change the hormones and amino acids produced during digestion, which could explain how the surgery eliminates symptoms of type 2 diabetes, according to a small new study.
The findings could lead to new treatments for type 2 diabetes, the researchers said. Untreated, diabetes can lead to heart disease, blindness, amputations and kidney disease.
In gastric bypass surgery, the stomach is divided into two sections. Food is then directed to the smaller section, so people feel full after eating less food.
This study included four women who had gastric bypass surgery. During the operation, a catheter was inserted into the larger, bypassed section of each patient's stomach.
After the surgery, the researchers sent food through the catheter into this part of the stomach and analyzed the hormones produced. Those findings were compared to hormone activity when a meal was digested in the smaller section of the stomach.
Patients' levels of insulin and other hormones were much higher when a meal was digested in the smaller part of the stomach, compared to the larger bypassed section. Amino acid levels also were higher in the smaller part of the stomach, while levels of free fatty acids were lower, according to the study, which was published April 30 in the Journal of Clinical Endocrinology & Metabolism.
The increased levels of hormones -- particularly insulin -- during digestion in the smaller part of the stomach enabled patients to maintain better control of their blood sugar, the researchers said. Despite the study's findings that gastric bypass could cause changes in hormones that lead to decreased diabetes symptoms, it did not necessarily prove a cause-and-effect link.
The findings "offer insights into how gastric bypass surgery works," said the study's main author, Nils Wierup, associate professor at the Lund University Diabetes Centre in Sweden. "The surgery is currently the most effective weapon we have to combat morbid obesity and, as a side effect, it has proven to relieve symptoms of type 2 diabetes."
"Exploring the impact this surgery has on digestion could yield new, non-surgical strategies for treating diabetes and obesity," Wierup added in a journal news release.
About 18.8 million children and adults in the United States are diagnosed with diabetes. Many more have the disease but don't know it.
The MedlinePlus Medical Encyclopedia has more about gastric bypass surgery.