Enteral nutrition is the food or nutritional substance that is introduced to the gastrointestinal tract of the animal, rather than being absorbed in the small intestine. The small intestine has only a limited amount of time to absorb nutrients from food and act as a waste disposal system. The food then moves into the colon, where it is used as a primary source of nourishment by the body. Enteral nutrition is usually administered through a tube feeding system. This tube is inserted through the mouth into the stomach, where it travels up the tract of the animal. The nutrients then enter the duodenum where they are absorbed into the bloodstream.
The primary difference between parenteral and enteral nutrition is that in the former, the nutrients are absorbed into the body more rapidly, thus stimulating an early physiological response. As well, the gastric juices are not secreted into the digestive tract, so there is no need to further stimulate the intestines or the rest of the body to digest the food. In this method, patients often feel hungrier than they did before they began receiving the nutrients. The energy levels are raised. However, this is offset by the fact that there is no absorption of nutrients after the surgery, so these cannot be said to be true full benefits of gastric bypass surgery. Enteral parenteral nutrition is currently undergoing clinical trials for the treatment of Crohn's disease in the U.S. This is due to the potential benefits to older adults with this condition. Crohn's is an inflammatory bowel disease that causes inflammation within the digestive system. It can affect any part of the digestive system, however, it is most commonly found in the small or medium intestines (caused by damage to the muscle lining).