The Digestive System
Understanding how your body works is a key to understanding how weight loss surgeries work. When you eat, the job of your digestive system is to break down and absorb food. Your body turns food into energy for use, and if it isn't used, excess energy is stored in your body as fat. After surgery, your body will use this fat for energy and as a result, you lose weight.
The key parts of your digestive system are:
- Mouth As you chew food, your salivary glands secrete enzymes that help begin the process of digestion.
- Esophagus When you swallow food, muscle action brings the food down your esophagus, or food pipe, and empties through a one-way valve into the stomach.
- Stomach This organ is considered the food 'reservoir' – storing food and sending it slowly to the small intestine. In the stomach, protein, fats and carbohydrates are partially digested into smaller portions. As food leaves the stomach through another one-way valve, it empties into the small intestine. Normally, the stomach can hold about three pints of food after a single meal.
- Small Intestine Also known as the small bowel, the small intestine is responsible for most digestion and absorption of food – protein, vitamins, minerals, and essential fats. The mixture of digestive juices helps break down the food so that it can be absorbed through the walls of the small intestine and into the bloodstream. The small intestine is divided into 3 sections: the duodenum - the first section and attached to the stomach; jejunum - the middle section responsible for most of the digestion and absorption of food; and the ileum - the third section and attached to the large intestine.
- Liver The liver produces bile – an important chemical aiding digestion. Bile drains into the gallbladder where it is stored until needed for digestion.
- Gallbladder The gallbladder is attached underneath the liver; it stores and concentrates bile. When food enters the stomach, it 'signals' the gallbladder to squeeze out bile into the duodenum for digestion.
- Pancreas The pancreas is located behind the stomach and produces enzymes essential to digestion. These enzymes are also released into the duodenum when food in the stomach 'signals' the start of the digestion process.
- Large Intestine Also known as the large bowel, most fluids are absorbed in the large intestine. The leftover waste products from food digestion are concentrated and passed through the rectum as stool.
