The Mouth

Also known as the oral cavity, the mouth is the hollow cavity that allows food and air to enter the body. Many other organs are found within the mouth, such as the teeth, the tongue, and the ducts of the salivary glands. These work together to aid the ingestion and digestion of food.

Digestion starts in the mouth, when taking the first bite of food. The mechanical process of chewing breaks the food down into more easily digestible pieces. Alongside this, saliva secretions mix with food and aid the process of breaking it down into a form the body can absorb and use.

Approximately 1.5 litres of saliva are produced every day, and this plays a vital role in lubricating food, digestion, and protecting the oral environment. Therefore, the regulation of saliva production is vital to ensure that efficient digestion takes place.

Saliva is made up of various components and is secreted via three paired exocrine salivary glands. The production of saliva, how it varies with consumption of food, and the consequences of low saliva secretion, all affect the digestion process.

Swallowing is the mechanism by which food is transported from the mouth to the stomach.

There are different phases of swallowing, and it is important to consider the clinical conditions that may result from the process going wrong.

In this section, learn more about the mouth and processes that occur for the start of digestion- the regulation of saliva, the secretion of saliva, and swallowing.