Welcome to HealthcareMagic, Let me try to completely explain this situation as we understand it today: Gastric bypass patients regain weight due to abnormal glucose tolerance. Almost 80% of patients who undergo gastric bypass surgeries to lose weight show abnormal glucose tolerance when administered a glucose challenge. Some patients are downright hyperglycemic to the point of meeting criteria to be diagnosed with diabetes. The working hypothesis, according to researchers, is that there is an enhanced insulin response which triggers low blood sugar with a corresponding increase in appetite. The rapid emptying of the gastric pouch is more than likely the cause for the enhanced insulin response. The combination of the rapid emptying of the pouch and low blood sugar are causes for increased appetite. This finding has raised questions regarding whether the gastric bypass should remain the gold standard for weight loss for the morbidly obese. At the very least, it has been suggested that a valve be inserted in the bypass procedure. Patients who experience this side-effect are often alarmed and unprepared for the rapid increase in their weight and surprised at the ravenous appetite that develops so soon after a meal. Sixty-three patients in a recent study were clinically studied as to who had undergone gastric bypass procedures. All the patients had a 100 g glucose tolerance test where the glucose was measured one and two hours after a meal. The investigators defined low blood sugar as less than 60 mg/dl or a decrease of 100 mg/dl or more within two hours of a meal challenge and no glucose value exceeding 200 mg/dl. They defined hyperglycemia as any value 200 mg/dl. Glucose tolerance tests showed six patients with hyperglycemia, including five who had normal fasting levels. Furthermore, 26 additional patients were identified who had reactive hypoglycemia (low blood sugar) and another eight who had both low and high blood sugars. The abnormal swings in blood glucose stimulated the researchers to comment that care must be taken when commenting that bariatric surgery can cure diabetes. In addition, this finding lends thought to what should be done in the future to better serve the needs of the bariatric population since the goal is to take weight off and keep it off while remaining healthy. The mechanisms for the rapid swing in appetite is apparently due to the changes in hunger hormones such as ghrelin which may increase or decrease, but, surprisingly long term studies relating to such hormonal changes remain absent and many patients remain clueless as to why such side-effects occur. Other studies show a post-operative decrease in insulin resistance and better glucose control. At the same time studies exist concluding that long-term patients of this procedure suffer from weight regain and a worsening of blood sugar control. Such procedural outcomes suggest that alterations in the gastric bypass procedures need to be considered such as the use of valves or possibly substituting the vertical-sleeve gastrectomy and duodenal switches that are not as severely malabsorptive. The take home message is that patients with diabetes who are opting for a bariatric weight loss procedure should weigh the long-term consequences of each type of surgery so they may make informed choices about their bodies. ©Kathy Shattler, MS, RDN Now, what do you do? Get a list of high vs. low glycemic carbohydrates. Switch to low glycemic carbohydrates as a mainstay of your nutrition plan. Cut your portions/calories down. Make certain you are getting all your nutrients ( are you still taking bariatric vitamins?). You can be active with your upper body even if the lower part has been compromised. At least get your heart rate up with arm weights (per Dr. approval). To answer your question, it could be the lack of activity or the bypass or both. Theoretically, it would take a difference of 576 calories in reduced activity per day to gain 60 lbs. per year if your eating habits have not changed. Does that sound reasonable to you? This is not your fault and it can be fixed. I suggest you locate a Registered Dietitian in your area to help you get back on track with an individualized meal plan, exercise routine, referrals, support and follow-up. My very best wishes to you. Kathryn Shattler, MS,RDN