The Gastric bypass surgery is a combination of both restrictive and malabsorptive elements. The Gastric bypass 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 the upper pouch.
This procedure leads to a marked reduction in the functional volume of the stomach, accompanied by an altered physiological and physical response to food. The restrictive portion of the bypass works to limit how much food you are able to consume before feeling a sense of fullness, usually about ¼-1/2 cup of food.
The malabsorptive component of the bypass stems from bypassing some of the stomach and small intestine. One part of the small intestine still allows the breakdown of food whereas the other segment of the small intestine is now connected to the small stomach pouch that will transport the food where it will connect to the last part of the small intestine. Because of this process, fewer calories will be absorbed, resulting in significant weight loss.
However, in addition to less absorption of calories, there is also less nutrient absorption as well. The area of the small intestine that is bypassed is responsible for most of the absorption of calcium, iron, B vitamins, folic acid and others. Because of the lack of vitamin absorption from your diet, it is crucial to be very diligent with your vitamin regimen both after surgery and for your lifetime. Serious health consequences can occur otherwise. Of course, thorough follow up lab checks will be performed routinely to check these vital nutrients.
Weight loss of 65-75% of excess body weight is common with this procedure. Medically, there is typically a dramatic reduction and resolution of patients’ comorbid conditions including hyperlipidemia, hypertension, type 2 Diabetes, gastroesophageal reflux disease and obstructive sleep apnea.
The gastric bypass is a powerful tool to help you reach your weight loss goals. However, it does require a commitment of healthy eating, regular exercise and consistent vitamin regimens to remain successful and healthy after this procedure.