One-anastomosis (Mini) gastric bypass is a relatively new operation first performed in 1997. This involves stapling the stomach starting from its lower part (known as the antrum) to create a long gastric pouch. The rest of the stomach remains in but food does not go into this (hence the name bypass).
The small intestine is then connected to the bottom of this pouch in such a way that the first part is bypassed.
Few research studies have examined the changes after this operation but it is thought to work mainly through altering gut signals which control appetite, taste and blood sugar but also through restricting the size of the stomach.
The re-plumbing means that bile contents can pass into the stomach and food pipe. At the moment it is unclear whether this might increase the risk of stomach cancer.
On average people lose 25-30% of their total body weight.
One-anastomosis (Mini) gastric bypass requires adherence to dietary recommendations, life-long vitamin/mineral supplementation, and follow-up compliance.
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