This is a more extensive and complex procedure than a sleeve gastrectomy. It is suitable for people with a BMI of 50 or less, as it is not safe to attempt in more obese patients.
A gastric bypass separates off a major part of the stomach, creating a small stomach pouch that reduces the amount of food you can eat.
The bypass part of the surgery then diverts the path of food after it leaves the stomach. Normally food leaves the stomach and passes through sections of small intestine that are around 6 metres long. A gastric bypass creates a new opening at the bottom of the stomach pouch, which is connected to a point further down the small intestine.
A Gastric Bypass therefor leads to weight loss in two ways:
- The small stomach pouch reduces the amount of food you can eat: this is the most important component.
- The bypass of some of the small intestine prevents you absorbing some of the calories and other nutrients from your food.