Heartburn is the symptom of a condition called gastro-oesophageal reflux disease, in which acid juice from the stomach returns into the oesophagus. This may lead to a harsh, burning sensation in the upper abdomen, moving through the chest and throat to the neck. The oesophagus or the food pipe, has a small ring of muscle called the lower oesophageal sphincter (LES). This acts as a valve, opening during swallowing and closing immediately to prevent moving back of the contents from the stomach to the oesophagus. When however, this valve fails to close adequately, the stomach acids may reflux back into the oesophagus causing a burning sensation. What contributes to a heartburn? * Fatty and spicy foods delay stomach emptying leading to an increased tendency to reflux. * Certain types of medications like ibuprofen. * Excessive alcohol intake and smoking. * Obesity, which may lead to an increased pressure in the abdominal cavity, causing the contents of the stomach to move back to the oesophagus. * A structurally weak sphincter muscle. * Hiatus hernia, in which the stomach may push through the diaphragm, preventing the muscle fibres of the diaphragm from closing the lower end of the oesophagus. What are the symptoms? # Painful burning in the upper chest or abdomen # Indigestion causing upset stomach # Regurgitation or throwing up # Difficulty in sleeping after eating # Hoarseness and sore throat # Bitter or sour taste in the throat.