Coughs are one of the most common symptoms of illness. Although a cough can sound awful, it's not usually a sign of a serious condition. In fact, coughing is a healthy and important reflex that helps protect the airways in the throat and chest.

Why do we cough?
A cough usually begins with irritation of nerve endings in the respiratory tract. A cough is useful and effective because the action can be stimulated when needed.  Normal expiratory muscles such as the diaphragm and abdomen wall are made to contract so that strong "push" can be given to air in the lungs. Therefore, coughing allows mucus to be dislodged and expelled from airways.

In general, there are three main ways to look at cough:

1. Cough helps us clear mucus and foreign material from our airways; in this respect, cough is useful and needs to be as effective as possible.
2. Cough can be a symptom of a disease or of a problem.
3. Cough spreads colds and other infections from one person to another.

Occasionally, coughing can help restore normal heart beat for a heart experiencing abnormal beating or rhythm.  But what health conditions can cause coughing?  Continue reading here for more information on possible causes of dry or persistent cough here.