The esophagus is the muscular tube which connects your throat (pharynx) with your stomach. It is through this tube that any food or drink your ingest passes. On average the esophagus is 25cm but may vary from person to person. The sphincter of the esophagus only opens when swallowing or regurgitating food. This is so that foreign objects or air do not make their way into the stomach.
What is the function of the esophagus?
The esophagus only has one major function in the body. This is to allow the passage of food, liquid and saliva from the mouth to the stomach. The esophagus moves food from the mouth to the stomach by a series of coordinated contractions of the muscular lining. This is an automatic process and is not normally felt by a person after swallowing. A person may feel these contractions if they swallow something too large or too quickly. They may also feel it if the liquid being swallowed is very hot or cold. The Esophagus has specialized glands that produce mucus to keep the passageway moist. This allows food to be passed through the tube more easily.
The esophagus also has a set of tightly clenched muscles at either end called sphincters. It is these sphincters that stop the flow of food and liquid back from the stomach. When a person swallows the sphincters relax and allow the food or liquid passed. They then quickly close to prevent leakage. This is how people are able to swallow lying down or even upside down. It is the relaxation of these muscles that cause reflux. When they open to allow gas to escape from the stomach small amounts of liquid may also flow back into the esophagus and the mouth.