Role of Gallbladder in Digestion
An understanding of the function of gallbladder is necessary to understand why gallbladder removal surgery is the solution for presence of gallstones. Gallbladder is the place where the bile, a potent digestive juice produced by the liver is stored in a very concentrated form. But before it is stored it is imperative to understand when it is stored. Every day about 800 – 1000 ml of bile is produced by the liver. There is a duct that runs from the liver to the duodenum that transports the bile produced. But there is a branch in that duct that branches straight into the Gallbladder.
Whenever a meal is consumed, the bile produced by the liver at that point directly flows into the duodenum of the small intestine. But when there is no meal consumed (during fasting or in the interval between two meals), the bile continuously produced by the liver does not flow into the duodenum but instead, it flows into the Gallbladder only to be converted to a concentrated form.
The typical important role of Gallbladder comes into play only when we consume very heavy meals during a feast or important occasions, or foods that are fatty and oily, including vegetarian foods. During such times, the duodenum releases a hormone called cholecystokinin which stimulates the Gallbladder. The Gallbladder contracts and releases the concentrated bile into the duodenum.
Bile is typically made up of bile salts, cholesterol, certain fats and pigments like bilirubin. The bile has two pronged action in the digestive process. First, the bile salt acts like a detergent on the fatty food and they emulsify the fat present. This emulsification breaks down the fat into small, microscopic fat globules. Second, they act as a carrier of the fat so broken down. The other digestive juices like pancreatic juice help in digesting the fat completely and making them ready to be absorbed by the intestinal wall. It may be noted that fat soluble vitamins are also transported by the bile salts during the digestion process and absorbed by the intestine.