When you undergo gastric bypass surgery, a surgeon is making your stomach smaller so that you will feel fuller faster. Part of your small intestine is usually being bypassed also. The end result? You consume and absorb fewer calories so you lose weight.

Generally, a person is a candidate for gastric bypass surgery when their body mass index is greater than 40 or they are at risk of death from a condition related to their obesity.

The most common bypass surgery is called Roux-en-Y gastric bypass. This is when an incision is made either through your abdominal wall (open surgery) or laparoscopic with cameras through “puncture wounds.” The stomach is made much smaller and is attached directly to the small intestine. By bypassing the duodenum, fat absorption is reduced.

The normal function of digestion (before surgery) is as follows. Intake enters through your mouth. As you chew what you’re eating, enzymes in your saliva start to attack and break down the carbohydrates in your meal. What you now have before you swallow is called a bolus. You swallow this bolus which travels down your esophagus and into your stomach. Once there, all the acids and juices in your stomach start flowing to further break down this bolus. A sphincter located at the end of your stomach opens up by way of contractions to allow the broken down bolus to enter the small intestine. It is here where the majority of absorption of fats, vitamins and minerals occurs. When your body has gotten most of its absorption, the broken down bolus continues down the intestine into the large intestine. The basic purpose of the large intestine is to absorb excess water and salts. Whatever has not been used by the body is then excreted as waste.

As you will notice from the Roux-en-Y procedure and several other gastric bypass procedures that I will mention, the GI tract is deviated in some way from the normal.

Another gastric bypass procedure is called Adjustable Gastric Binding. With this procedure, nothing is removed or altered. A tight band is placed around near the top of the stomach to help restrict the intake of the person. This also delays the emptying of the stomach resulting in fewer calories consumed over a longer period of time.

Vertical Banded Gastroplasty is a procedure where the upper part of the stomach near the esophagus is stapled vertically, making a small pouch. A band is then placed at the end of the pouch to delay emptying. This procedure also does not alter absorption.

The Biliopancreatic Diversion procedure’s goal is to cause mal-absorption of food and restrict intake. In BPD, large portions of the stomach are removed. When intake exits what’s left of the stomach, it goes directly into a channel where it meets liver bile and pancreatic juices. The “food” then enters the colon. This procedure is rather drastic due to the fact that nutrients have almost no place to be absorbed.

Lastly and least common of all gastric bypass procedures is: Biliopancreatic Diversion with Duodenal Switch. In this procedure, most of the stomach is left alone. At the exit of the stomach, its contents are sent to a new short duodenal segment. Much like BPD, the contents end up mixing with liver bile and pancreatic juices. This procedure includes dividing both the large and small intestine in half. Again, the goal of this procedure is to decrease food intake and absorption.

As with any procedure, this one comes with many risks. Blood loss, infection and surgery complications are generally the most upfront possible risks/complications. People generally lose about 10 pounds a month. Excess skin that ‘just hangs’ is another common complaint. You could be required to undergo several more surgeries, develop hernias and gallstones, experience inflammation of the lining of your stomach, osteoporosis, and anemia, not be satisfied with your results or even die.

Gastric bypass surgery is not a quick fix for weight problems. It does not fix the psychological reasons why we over eat.

Most procedures leave the person only capable of eating ounces at a time. The days of eating an entire hotdog or drinking a glass of soda or water are almost non-existent. You literally surgically make yourself anorexic.

Not only does the amount of what you can eat change, so does the menu. Anything with fat, alcohol or sugar is probably going to cause you problems.

With many of the procedures, it is possible to ‘cheat’ and stretch out your new stomach pouch. People who have had gastric bypass procedures also often complain about “Dumping Syndrome.” Dumping syndrome occurs when you eat more then your stomach can handle or you eat things that you really shouldn’t. The contents of your stomach get dumped rapidly into your small intestine. This causes cramping, bloating, sweating, nausea and diarrhea.

Not everyone is a candidate for gastric bypass procedures. Only your doctor can tell you if you are. You will possibly have a psychological evaluation to determine if you’re ready to make the lifestyle changes after the procedure.

This is a major choice-several of your choices are irreversible. Do your research before going under the knife and make sure you fully realize what all is involved. Science has not yet established the long term effects of gastric bypass surgery.

© Rebecca Pillar 2007