The Procedure
This procedure works by several mechanisms. First, the new stomach pouch holds a considerably smaller volume than the normal stomach and helps to significantly reduce the amount of food (and thus calories) consumed. The greater impact, however, seems to be the effect the surgery has on gut hormones, which impact a number of factors, including hunger, satiety, and blood sugar control.
Short-term studies show that the sleeve is as effective as the Roux-en-Y gastric bypass in terms of weight loss and improvement or remission of diabetes. There is also evidence that suggests the sleeve, similar to the gastric bypass, is effective in improving type 2 diabetes independent of weight loss. The sleeve’s complication rates fall between those of the adjustable gastric band and the Roux-en-Y gastric bypass.

Advantages
- Restricts the amount of food the stomach can hold
- Induces rapid and significant weight loss that comparative studies find similar to that of the Roux-en-Y gastric bypass. Weight loss of >50% for 3-5+ year data, and weight loss comparable to that of the bypass with maintenance of >50%
- Requires no foreign objects (AGB), and no bypass or re-routing of the food stream (RYGB)
- It involves a relatively short hospital stay of approximately two days
- Causes favorable changes in gut hormones that suppress hunger, reduce appetite, and improve satiety
Disadvantages
- It is a non-reversible procedure
- Has the potential for long-term vitamin deficiencies
- It has a higher early complication rate than the AGB
