Gastric bypass surgery, also known as Roux-en-Y gastric bypass, is a weight-loss procedure that involves creating a small stomach pouch and rerouting the small intestine to this new pouch. This surgery helps patients lose weight by reducing the amount of food the stomach can hold and altering the digestive process to limit calorie absorption. It is commonly recommended for individuals with severe obesity who have not achieved weight loss through diet and exercise alone. The procedure aims to improve overall health and reduce the risk of obesity-related conditions such as diabetes, hypertension, and sleep apnea.