The esophagus Throat and Esophagus The throat (pharynx) lies behind and below the mouth. When food and fluids leave the mouth, they pass through the throat. Swallowing of food and fluids begins voluntarily and continues automatically... read more is the hollow tube that leads from the throat (pharynx) to the stomach. Food does not just fall through the esophagus into the stomach. The walls of the esophagus propel food to the stomach by rhythmic waves of muscular contractions called peristalsis.
How the Esophagus Works
As a person swallows, food moves from the mouth to the throat, also called the pharynx (1). The upper esophageal sphincter opens (2) so that food can enter the esophagus, where waves of muscular contractions, called peristalsis, propel the food downward (3). The food then passes through the diaphragm (4) and lower esophageal sphincter (5) and moves into the stomach.  |
Just below the junction of the throat and the esophagus is a band of muscle called the upper esophageal sphincter. Slightly above the junction of the esophagus and the stomach is another band of muscle called the lower esophageal sphincter. When the esophagus is not in use, these sphincters close so that food and stomach acid do not flow back up the esophagus from the stomach to the mouth. During swallowing, the sphincters open so food can pass to the stomach.
With aging, the strength of esophageal contractions and the pressure in the sphincters decrease. This condition makes older people more prone to backflow of acid from the stomach (gastroesophageal reflux or GERD Gastroesophageal Reflux Disease (GERD) In gastroesophageal reflux disease, stomach contents, including acid and bile, flow backward from the stomach into the esophagus, causing inflammation in the esophagus and pain in the bottom... read more 
), especially when lying down after eating.
Two of the most common symptoms of esophageal disorders are dysphagia (an awareness of swallowing difficulty Difficulty Swallowing Some people have difficulty swallowing (dysphagia). In dysphagia, foods and/or liquids do not move normally from the throat (pharynx) to the stomach. People feel as though food or liquids become... read more ) and chest or back pain Chest or Back Pain Pain in the middle of the chest or upper back can result from disorders of the esophagus or from disorders of the heart or aorta ( see Chest Pain). Symptoms may be similar. Gastroesophageal... read more . Dysphagia and chest or back pain may occur in any esophageal disorder, the most serious of which is esophageal cancer Esophageal Cancer Esophageal cancers develop in the cells that line the wall of the esophagus (the tube that connects the throat to the stomach). Tobacco and alcohol use, human papillomavirus infections, and... read more 
.
Esophageal and swallowing disorders include the following:
Difficulty swallowing Difficulty Swallowing Some people have difficulty swallowing (dysphagia). In dysphagia, foods and/or liquids do not move normally from the throat (pharynx) to the stomach. People feel as though food or liquids become... read more (dysphagia) can result from many of these esophageal disorders but also from problems with the nervous system.
In another esophageal disorder, called esophageal varices Esophageal Varices Esophageal varices are enlarged veins in the esophagus, which can cause major bleeding. Esophageal varices are caused by high blood pressure in blood vessels in and around the liver (portal... read more 
, the veins at the lower end of the esophagus become dilated and bleed easily.
