The lower esophageal sphincter normally relaxes to allow food and fluid to flow down to the stomach, the Mayo Clinic explains. The sphincter then closes. When it is not working properly or weakens, it may allow the stomach acid to flow back up into the esophagus, which results in heartburn, characterized by a burning sensation in the chest and sometimes a sour taste in the back of the throat.
Foods
Although the kinds of foods that cause heartburn vary from person to person, there are some foods that tend to cause heartburn more than others. These include fatty or fried foods, citrus fruits, tomato products, chocolate, mints, onions, coffee, carbonated drinks and alcohol, according to the American Academy of Family Physicians (AAFP).
Overeating
Eating too much during a meal can contribute to heartburn. Doctors recommend eating smaller meals for people who notice heartburn symptoms after eating. Being overweight can also contribute to heartburn, because excess fat puts pressure on the abdomen. Tight-fitting clothes can do the same thing.
Lying Down
Lying down or bending over soon after eating can cause heartburn. Avoid lying down or any physical activity involving bending over for at least 3 hours after eating. Heartburn can occur in the middle of the night following a meal that included offending foods, because stomach acid can come back up into the esophagus in people who are in a sleeping position. Raising the bed 6 to 8 inches using blocks under the bedposts can help prevent this problem. Extra pillows do not always work because the upper body needs to be raised.
Medicine
Aspirin or ibuprofen may cause heartburn in some people. Sedatives and some medicines for high blood pressure may also cause heartburn symptoms, the AAFP says.
Smoking
Smoking may stimulate acid production in the stomach. It may also weaken the lower esophageal sphincter, causing heartburn.
Medical Conditions
Pregnancy may increase symptoms of heartburn, the Cleveland Clinic notes. A condition called hiatal hernia is a bulging of the stomach into the chest that can cause heartburn. Some people suffer from gastroesophageal reflux disease (GERD), in which heartburn and acid reflux occur two or more times a week. Those suffering from GERD should take over-the-counter acid relievers or prescribed medication to treat the problem.
