Gut microbiota in gastrointestinal diseases.

Gut microbiota is a highly dense population of different kinds of bacteria residing in the gut which co-evolves with the host. It engages in a number of metabolic and immunological activities. Gut microbiota is associated with maintenance of health, and unbalanced microbiota contributes in the development of several diseases. Alteration of beneficial gut microbiota population triggers gastrointestinal diseases including irritable bowel syndrome, inflammatory bowel disease, celiac disease, colorectal cancer, and many others. Gut microbiota can be affected by multiple factors such as diet, stress, genetic variations. In this chapter, we highlight how gut microbiota plays a key role in pathogenesis of gastrointestinal disease.