Gastric sleeve
During gastric sleeve or sleeve gastrectomy surgery, the size of the stomach is reduced by stapling along its length to form a long tube. Gastric sleeve surgery is a restrictive procedure where the stomach volume is reduced by about 80%. After surgery, the hormone responsible for stimulating hunger is reduced, however, appetite does return around 1-2years post-surgery, so it is important to implement healthy lifestyle changes during this time. This will enable you to manage your hunger and fullness signals when your appetite returns. Each person experiences a different rate of weight loss after surgery, however, the majority of people lose most of their excess body weight in the first year after surgery. It is important to make the most of this time and treat it as a window of opportunity to implement healthy food choices, regular physical activity and create healthy long-term habits. Your ongoing success post-surgery depends on how well you have implement healthy lifestyle changes, your effort to continue with these changes for life and your adherence to follow up with your team. Evidence suggests that regular follow up with your team leads to more successful weight loss maintenance.

Roux-en-Y gastric bypass
Roux-en-Y gastric bypass surgery involves stapling the top of the stomach to form a pouch of 30-50ml in volume. The new, smaller stomach is then re-connected to the second part of the small intestine (jejunum) and bypasses the first part of the small intestine (duodenum). The smaller stomach pouch allows you to eat only a small portion of food before feeling satisfied, therefore, it is a restrictive procedure. The appetite stimulating hormone, ghrelin, is reduced which reduces your appetite. Greater nutrient absorption occurs in the duodenum which is bypassed in this procedure which means less vitamins and minerals are absorbed. Therefore, the roux en y gastric bypass is a malabsorptive as well as a restrictive procedure. Evidence suggests that roux-en- y leads to a higher rate of diabetes remission for patients with pre-existing type 2 diabetes mellitus and is the treatment of choice for patients who experience reflux. After surgery, evidence suggests that most weight is lost in the first 6months post-surgery, then it slows in the second 6 months and stabilises by the second year, however, each person has a different rate of weight loss. It is important to make the most of this time and treat it as a window of opportunity to implement healthy food choices and regular physical activity and make this a long term habit. Your ongoing success post-surgery depends on how well you have implemented healthy lifestyle changes, your effort to continue with these changes for life and your adherence to follow up with your team. Evidence suggests that regular follow up with your team leads to more successful weight loss maintenance.

One-anastomosis gastric bypass
The one-anastomosis gastric bypass which is also referred to the omega loop or ‘mini’ gastric bypass, is the newest procedure of the three listed here. During the procedure, the stomach is divided into a long narrow pouch which is connected to the second part of the small intestine (jejunum), bypassing the first part of the small intestine (duodenum). Unlike the roux-en-y gastric bypass which requires two connections (anastomoses), the one0anastomosis gastric bypass only requires one. Similar to the roux-en-y gastric bypass, the one-anastomosis gastric bypass is a malabsorptive and restrictive procedure. The smaller stomach pouch allows you to eat only a small portion of food before feeling satisfied, the appetite stimulating hormone, ghrelin, is reduced and less vitamins and minerals are absorbed due to bypassing the duodenum. Initial evidence suggests the single-anastomosis bypass is similar to the Roux-en-Y gastric bypass in terms of its ability to induce type 2 diabetes remission and when the majority of weight loss occurs.