Heartburn occurs when stomach acid backs up into the esophagus. This can occur for a number of reasons. The most common cause of heartburn is when the lower esophageal sphincter (LES) -- the valve that is located between the esophagus and the stomach and keeps stomach acid in the stomach -- relaxes at the wrong time or too easily. As a result, stomach acid backs up into the esophagus, causing the symptoms of heartburn. This stomach acid can also damage the lining of the esophagus, which may lead to erosive esophagitis or Barrett's esophagus.
Other causes of heartburn are:
- Certain foods, such as chocolate, fatty foods, peppermint, and carbonated beverages can weaken or relax the LES
- Eating large meals or shortly before bedtime
- A hiatal hernia
- Pressure on the stomach, including frequent bending over, tight clothes, lifting, obesity
- Certain medications
- Stress, which can increase acid production and slow down the emptying of the stomach
"Heartburn and GERD FAQ." American College of Gastroenterology. 19 May 2009.
"Heartburn, Gastroesophageal Reflux (GER), and Gastroesophageal Reflux Disease (GERD)." NIH Publication No. 07–0882 May 2007. National Digestive Diseases Information Clearinghouse (NDDIC). 19 May 2009.
Howard Hampel, MD, PhD; Neena S. Abraham, MD, MSc(Epi); and Hashem B. El-Serag, MD, MPH, "Obesity and the Risk for Gastroesophageal Reflux Disease and Its Complications." 2 August 2005 | Volume 143 Issue 3 | Pages 199-211. Annals of Internal Medicine - The American College of Physicians. 19 May 2009.