Heartburn is an uncomfortable burning feeling in your chest that has nothing to do with your heart. It happens when stomach acid splashes back up into your esophagus, the tube connecting your mouth to your stomach. Your stomach produces powerful acid to break down food, and it has a special lining to protect itself from that acid. Your esophagus doesn't have that protection, so when acid touches it, you feel a burning sensation rising from your stomach toward your throat.

Certain foods can trigger heartburn: spicy dishes, tomato sauce, chocolate, or fizzy drinks. Eating too much at once or lying down right after a big meal can also cause it. Some people experience heartburn occasionally after eating something that disagrees with them, while others deal with it regularly.

The word itself is somewhat misleading, since the burning feeling happens in your esophagus, not your heart. But people called it heartburn because the sensation occurs behind your breastbone, near where your heart is located. Despite the scary name, heartburn is a digestive problem, not a heart problem. If someone experiences frequent or severe heartburn, they should talk to a doctor, who might call it by its medical name, acid reflux.