Heartburn has nothing to do with your heart. It's a burning feeling behind your breastbone, along with a bitter, sour taste in your mouth.
How heartburn happens:
When you eat, food goes from your mouth down a tube called the esophagus into your stomach. In between the esophagus and the stomach is an opening called the lower esophageal sphincter. This muscular valve acts like a door to let food into your stomach. It normally closes quickly behind the food to keep stomach acids — which break down the food — from backing up into your esophagus.
If that valve doesn't close all the way, stomach acid backs up, or refluxes, into the esophagus. Stomach acid irritates the lining of the esophagus and causes a painful burning sensation. The feeling may be worse after bending over or when you lie down.
Certain foods and drinks — like tomato products, alcohol, citrus, coffee, and fatty or spicy foods — may be more likely to irritate the lower esophageal sphincter and make heartburn worse. Being overweight, eating big meals, wearing clothes that are tight around the waist, and smoking also raise your risk for heartburn.
Learning what triggers your heartburn can help you ease the burn.
Reviewed by Michael W. Smith, M.D.