Weight Loss after Bariatric surgery is due to restriction, malabsorption, and malnutrition. The results are fast initially due to the physical inability to consume enough calories to maintain the current weight, so stored fat/ muscle is then used to keep your body functioning. A starvation state will mean the loss of precious muscle tissue and bone density, and retention of adipose tissue or fat, so correct nutrition and supplements are important for life.

Gastric bypass surgery refers to a surgical procedure in which the stomach is divided into a small upper pouch and a much larger lower "remnant" pouch and then the small intestine is rearranged to connect to both.

The duodenal switch (DS) procedure, also known as biliopancreatic diversion with duodenal switch (BPD-DS) or gastric reduction duodenal switch (GRDS), is a weight loss surgery procedure that is composed of a restrictive and a malabsorptive aspect.

The sleeve gastrectomy (SG) is a restrictive weight loss operation. The outer part of the stomach is removed and the shape of the stomach is changed from a sac to a long narrow tube (sleeve). The gastric volume is reduced from approximately 2L to 100-150 mL

A laparoscopic adjustable gastric band is an inflatable silicone device placed around the top portion of the stomach to treat obesity, intended to slow consumption of food and thus reduce the amount of food consumed.

The intragastric balloon is an inflatable medical device that is temporarily placed into the stomach to reduce weight. It is marketed to provide weight loss when diet and exercise have failed and surgery is not wanted or not recommended.