What is Roux-en-Y gastric bypass surgery?

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

Roux-en-Y gastric bypass surgery is more commonly performed than gastric sleeve or adjustable gastric band (Lap Band) surgery for weight-loss purposes. This operation causes weight loss by both restricting the size of the stomach and reducing the amount of food the body can absorb. In this procedure, the surgeon makes a small pouch at the top of the stomach, and then connects the pouch to a Y-shaped section of the small intestine, which allows food to bypass the lower stomach and a portion of the intestines.

Studies have shown that patients lose between 60% and 80% of excess body weight during the first year after surgery. Recent data shows a mortality rate of approximately 0.3%.

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Roux-En-Y gastric bypass is a surgery that helps you to lose weight by making your stomach smaller which limits how much you can eat. It also changes how your small intestine processes the food you eat. This surgery helps you to feel full on smaller amounts of food. The surgery also changes hormones such as grehlin that will help reduce hunger and even helps improve type 2 diabetes. Following surgery, blood sugar levels start returning to normal levels even before you start losing weight.

Dr. Melissa B. Bagloo, MD
Bariatric Medicine (Obesity Medicine) Specialist

The Roux-en-Y gastric changes the size of the stomach to a small gastric pouch and rearranges the small bowel to allow for the diversion of food away from the upper portion of the small intestines. Because of this, hormonal changes occur that affect the metabolic response of the body to food intake Blood glucose improves much more dramatically and much faster after the Roux-en-Y gastric bypass than after gastric band placement.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.