Beginning with an exploration of digestion at the cellular level, this volume of the Encyclopedia of the Human Body discusses the parts of the digestive system and how they work together and interact with other major body systems. The upper and lower gastrointestinal tract and accessory organs, such as the gall bladder and liver, are covered. The endocrine, circulatory, and lymphatic system are discussed in relation to the digestive system. The history of the research on the digestive system is presented and the future of research in this field is considered. Basic principles of human nutrition and it relates to the digestive system are explored. Digestive system disorders, symptoms and treatments are discussed, including colon cancer, ulcers, hepatitis, and diabetes. This reference concludes with a comprehensive glossary, recognized sources of nutritional information, and resources for further information including Web sites and contact information for organizations and national health institutions.