The four ways in which saliva is useful to us are:
- It moistens and lubricates the mouth cavity and the tongue to make speaking and swallowing easy.
- It cleans the mouth and destroys germs.
- The saliva binds the food particles and makes it into a mass called the bolus.
- Digestion begins in the mouth. Saliva contains an enzyme (amylase) which helps in the breakdown of starch to simple sugars (maltose).