Gut Microbiota and Health: A Review With Focus on Metabolic and Immunological Disorders and Microbial Remediation

Understanding and defining health is an important yet fuzzy topic. Despite several attempts, health is not a well-defined concept, therefore we seek to understand health from the perspective of the microbiome. Gut microbiota are an essential component in the modern concept of human health. However, the precise patterns of composition and functional characteristics of a healthy gut microbiome remain ill-defined. Microbial colonization patterns associated with disease states have been documented with the advancement of sequencing technologies. Several prebiotics and probiotics have been reported to restore the normal gut flora after being disrupted by various factors. Fecal microbial transplantation from healthy individuals into recipients suffering from diseases related to gut dysbiosis has also been reported to be effective in restoring the normal makeup of gut microbiota, as shown by its efficacy in treating Clostridium difficile infection, colitis, constipation, irritable bowel syndrome, and neurological conditions such as multiple sclerosis and Parkinson`s disease. In this review we attempt to define the parameters of healthy human gut flora and its disruption in diseased conditions, and restoration through administration of prebiotics, probiotics, and fecal microbial transplantation.