The human gut is home to many types of bacteria that produce metabolites that are used to maintain homeostasis in various physiological processes, including:

• vitamin synthesis
• pathogen protection
• immunological development
• intestinal angiogenesis
• intestinal epithelium cell development

Every person has a unique and dynamic niche of microorganisms in their gut. If the microbiota harbors harmful pathobionts or if keystone species that regulate the ecological community become threatened in some way, a condition known as microbial dysbiosis develops.