Weight loss has been known to alleviate the severity of type 2 diabetes. Thus, patients that have had weight loss surgeries such as gastric bypass have been observed to have improvements in their diabetes. Some have even been able to stop taking diabetes medications, as their blood glucose levels have normalized after weight loss due to the surgery. Research published in the journal Science Translational Medicine, has revealed part of the mechanism by which this improvement in diabetes occurs. Investigators from Columbia University in New York and Duke University in North Carolina, studied patients with diabetes that lost weight after gastric bypass and after dieting alone. In both groups, the patients lost the same amount of weight – about 20 pounds. The study also involved measuring metabolic compounds in the bodies of the two study groups. It was found that in the gastric bypass group, the levels of circulating branch chain amino acids was significantly lower. These metabolic compounds have been shown to impact obesity, diabetes, and insulin resistance. Insulin resistance has been one of the key mechanism by which type 2 diabetes develops in humans. Gastric bypass patients have been observed to have better control of their diabetes even before losing any weight. Thus, the gastric bypass surgery changes the metabolism of the body in a mechanism which is different from weight loss alone. These conclusions can only be postulated to occur in gastric bypass patients, which undergo a Roux-en-Y surgery that reduces the size of the stomach. Patients who have a Lap-Band weight loss device, which wraps around the upper stomach and limits the amount of food eaten, may not benefit from this mechanism. Further investigation may lead to medications which utilize the same mechanism as gastric bypass surgery in the treatment of diabetes without having to actually go through the surgical procedure.
Laferrere, B. et. al. (2011) “Differential Metabolic Impact of Gastric Bypass Surgery Versus Dietary Intervention in Obese Diabetic Subjects Despite Identical Weight Loss” Sci. Transl. Med. Vol. 3, Issue 80, p. 80re2