Despite its name, heartburn doesn't affect the heart. Heartburn is a burning feeling in the lower chest, along with a sour or bitter taste in the throat and mouth. It usually occurs after eating a big meal or while lying down. The feeling can last for a few minutes or a few hours.

What causes heartburn?
When you eat, food passes from your mouth down a tube (about 10 inches long in most people) called the esophagus. To enter the stomach, the food must pass through an opening between the esophagus and stomach. This opening acts like a gate to allow food to pass into the stomach.

Usually, this opening closes as soon as food passes through. But if it doesn't close all the way, acid from your stomach can get through the opening and into your esophagus. This is called reflux. Stomach acid can irritate the esophagus and cause heartburn.

Hiatal hernia can also cause heartburn. Hiatal hernia is a condition in which part of the stomach is pushed up through the diaphragm (the muscle wall between the stomach and chest) and into the chest. Sometimes this causes heartburn.

What factors add to heartburn?
Many things can make heartburn worse. Heartburn is most common after overeating, when bending over or when lying down. Pregnancy, stress and certain foods can also make heartburn worse.

Things that can make heartburn worse
-- Cigarette smoking
-- Coffee (both regular and decaffeinated) and other drinks that contain caffeine
-- Alcohol
-- Carbonated drinks
-- Citrus fruits
-- Tomato products
-- Chocolate, mints or peppermints
-- Fatty foods or spicy foods (such as pizza, chili and curry)
-- Onions
-- Lying down too soon after eating
-- Being overweight or obese
-- Aspirin or ibuprofen (one brand name: Motrin)
-- Certain medicines (such as sedatives and some medicines for high blood pressure)