How well do you know your own body? To help you understand your body and the problems you may encounter, we are beginning a series of basic anatomy lessons, beginning with the digestive system.

• The digestive system – which is also known as the gastrointestinal tract – breaks down, digests and absorbs food, and removes solid waste from the body.
• The digestive system is a continuous muscular tube, anything from 5–9 metres (15–20 feet) long, which extends from the mouth to the anus. It consists of the gullet (oesophagus), stomach, small intestine, large intestine (colon), back passage (rectum) and anus.
• The oesophagus carries swallowed food to the stomach. In the stomach it is mixed with acidic juices to aid digestion.
• The food then gradually passes into the small intestine where digestion and absorption is completed with the aid of juices from the liver and pancreas. Any waste is transported to the large intestine and excreted via the rectum and anus.
• The liver, gall bladder, bile ducts and pancreas are important organs that are often considered as part of the digestive tract. They play a major role in the digestion of food and in the breakdown of potentially harmful waste substances.
• Common disorders that affect the digestive tract include infection and inflammation, motility (movement) disturbances and cancers.

First published on embarrassingproblems.com
Reviewed and edited by Dr Kevin Barrett
Last updated: May 2025 by Dr Kevin Barrett