Restrictive and Malabsorptive

Restrictive And Malabsorptive

Bariatric weight loss surgeries aid weight loss through two methods; restricting the amount of food a patient can eat and preventing the body from absorbing all calories consumed. These two methods combined ensure rapid and sustainable weight loss and are known as the 'restrictive' and malabsorptive' elements of weight loss surgery.

Restrictive Element of Weight Loss Surgery

The success of weight loss surgery is largely due to the size of the stomach being reduced during surgery. Bariatric surgeons either remove part of the stomach, permanently reducing the stomach volume or restrict the stomach using reversible techniques.

In gastric bypass surgery, the stomach is surgically divided into smaller pouches. One of these pouches functions as a size-restricted stomach, the other pouch is disconnected from the digestive system and cannot store food. This surgery is restrictive as the newly created stomach pouch is significantly smaller, preventing large the patient eating large quantities of food.

Sleeve gastrectomy is a more extreme version of restrictive bariatric surgery. Unlike gastric bypass where the stomach is divided but remains inside the body, sleeve gastrectomy involves removing up to 80% of the stomach, leaving only a small stomach pouch. It is very difficult to reverse a gastric bypass and impossible to reverse a sleeve gastrectomy. 

Reversible, temporary bariatric procedures for weight loss are gastric banding and gastric balloon. Both of these surgeries restrict the size of the stomach usnig reversible methods:

Gastric Banding surgery is a procedure where the stomach is split into two with a silicon band  - forcing the stomach to act as an egg-timer, slowly processing food from one pouch to the other. As the 'upper' pouch is smaller, patients feel fuller after eating a much reduced quantity of food. When the patient reaches the target weight, the band can be removed and weight loss retained by following a balanced diet.

Gastric balloon is a non-invasive bariatric procedure. A balloon is inserted into the stomach and inflated. The inflated baloon 'fills' the stomach, again making the patient feel full after eating less food. Once at target weight, the balloon can be deflated and removed. Bariatric surgeons are able to deflate the balloon gradually, slowly increasing the size of the stomach and helping the patient retain the weight loss.

Malabsorptive Element of Weight Loss Surgery

 The malabsorptive element of bariatric surgery restricts the amount of calories a patient consumes from food eaten. Normally, food eaten enters the stomach and passes though the entire digestive tract. As food travels down the digestive tract, the body absorbs nutrients and calories from the food. The malabsorptive aspect of weight loss surgery, narrows the route food travels down the digestive tract. By shortening the distance food travels through the body, the fewer calories that can be absorbed.

It is very important that patients whose bariatric surgery combines malabsorptive and restrictive methods are aware of the nutritional deficiencies that can arise. As the body absorbs fewer calories, it also absorbs fewer nutrients. Patients who undergo surgery such as gastric bypass which combine both techniques are advised to seek nutritional guidance to avoid post-surgery nutritional deficiencies. 

Find bariatric surgeons your area to learn more about the restrictive and malabsorptive aspects of weight loss surgery.