Barrett's esophagus is a condition in which the
esophagus, the muscular tube that carries food and saliva
from the mouth to the stomach, changes so that some of its
lining is replaced by a type of tissue similar to that
normally found in the intestine. This process is called
intestinal metaplasia.
While Barrett's esophagus may cause no symptoms itself,
a small number of people with this condition develop a
relatively rare but often deadly type of cancer of the
esophagus called esophageal adenocarcinoma. Barrett's
esophagus is estimated to affect about 700,000 adults in
the United States. It is associated with the very common
condition gastroesophageal reflux disease or GERD.
Normal Function of the Esophagus
The esophagus seems to have only one important function
in the body—to carry food, liquids, and saliva from the
mouth to the stomach. The stomach then acts as a container
to start digestion and pump food and liquids into the
intestines in a controlled process. Food can then be
properly digested over time, and nutrients can be absorbed
by the intestines.
The esophagus transports food to the stomach by
coordinated contractions of its muscular lining. This
process is automatic and people are usually not aware of
it. Many people have felt their esophagus when they
swallow something too large, try to eat too quickly, or
drink very hot or very cold liquids. They then feel the
movement of the food or drink down the esophagus into the
stomach, which may be an uncomfortable sensation.
 |
| Digestive tract |
The muscular layers of the esophagus are normally
pinched together at both the upper and lower ends by
muscles called sphincters. When a person swallows, the
sphincters relax automatically to allow food or drink to
pass from the mouth into the stomach. The muscles then
close rapidly to prevent the swallowed food or drink from
leaking out of the stomach back into the esophagus or into
the mouth. These sphincters make it possible to swallow
while lying down or even upside-down. When people belch to
release swallowed air or gas from carbonated beverages,
the sphincters relax and small amounts of food or drink
may come back up briefly; this condition is called reflux.
The esophagus quickly squeezes the material back into the
stomach. This amount of reflux and the reaction to it by
the esophagus are considered normal.
While these functions of the esophagus are obviously an
important part of everyday life, people who must have
their esophagus removed, for example because of cancer,
can live a relatively healthy life without it.
