what can cause heartburn
Heartburn Causes. The cause of heartburn is excessive flow of gastric contents back into the esophagus. Normally, there is an occasional backflow into the esophagus with no symptoms. The acidic gastric contents, when present in large amounts, irritate the esophagus (usually the lower part) and cause the symptoms of heartburn.
The basic cause of heartburn is a lower esophageal sphincter, or LES, that doesn't tighten as it should. Two excesses often contribute to this problem: too much food in the stomach (overeating) or too much pressure on the stomach (frequently from obesity, pregnancy, or constipation).
Despite its name, heartburn has nothing to do with the heart. Some of the symptoms, however, are similar to those of a heart attack or heart disease. Heartburn is an irritation of the esophagus that is caused by stomach acid. This can create a burning discomfort in the upper abdomen or below the breast bone. With gravity's help, a muscular valve called the lower esophageal sphincter, or LES, keeps stomach acid in the stomach.