To understand how surgical procedures aid the grossly overweight person to reduce their body fat, it helps to first understand the digestive process that is responsible for handling the food we take in.
Once food is chewed and swallowed, its on its way through the digestive tract, where enzymes and digestive juices will break it down and allow our systems to absorb the nutrients and calories. In the stomach, which can hold up to three pints of material, the breakdown continues with the help of strong acids. From there it moves into the duodenum, and the digestive process speeds up through the addition of bile and pancreatic juices. Its here, that our body absorbs the majority of iron and calcium in the foods we eat. The final part of the digestive process takes place in the 20 feet of small intestine, the jejunum and the ileum, where calorie and nutrient absorption is completed, and any unused particles of food are then shunted into the large intestine for elimination.
Weight loss procedures involve bypassing, or in some way circumventing the full digestive process. They range from simple reduction of the amount you can eat, to major bypasses in the digestive...