The movement of food from mouth to stomach requires normal and coordinated action of the mouth and throat, propulsive waves of muscular contractions of the esophagus (called peristalsis), and relaxation of the sphincters (the bands of muscle that need to open so that food can pass from the esophagus into the stomach).
(See also Overview of the Esophagus.)
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. |
A problem with any of these functions can cause difficulty swallowing (dysphagia), heartburn, chest pain, regurgitation (the spitting up of food from the esophagus or stomach without nausea or forceful contractions of abdominal muscles), vomiting, or aspiration of food (sucking food into the airways when inhaling).
Disorders of the throat also can cause problems with the movement of food.
The main causes of abnormal propulsion of food are movement (motility) disorders of the esophagus. The most common disorders include
Sometimes, disorders that affect the whole body also affect movement of the esophagus. Examples include systemic sclerosis and Chagas disease.
Doctors use various methods to diagnose movement disorders of the esophagus. Methods include endoscopy with biopsies, barium swallow x-rays, manometry, acid reflux tests, and impedance planimetry.
Treatment of abnormal propulsion of food depends on the cause.
Spotlight on Aging: Problems with Swallowing
As people age, several changes may affect the ability to swallow. Slightly less saliva is produced. As a result, food is softened (macerated) less well and is drier before it is swallowed. The muscles in the jaws and throat may weaken slightly, making chewing and swallowing less efficient. Also, older adults are more likely to have conditions that make chewing and swallowing difficult. For example, they are more likely to have loose teeth or to wear dentures. With aging, the contractions that move food through the esophagus become weaker. This change is very slight and usually has little effect on moving food to the stomach. But if older adults try to eat while lying down or lie down just after eating, food may not easily move to the stomach. If reflux develops, the aging esophagus may be slower to move refluxed stomach acid back into the stomach. Some older adults have a hiatus hernia, which may contribute to reflux. |
