The Gut Microbiome and Its Role in Human Health and Disease: A Comprehensive Review
Keywords:
Gut Microbiome, Dysbiosis, Intestinal Microbiota, Short-Chain Fatty Acids, Gut-Brain Axis, Fecal Microbiota Transplantation, Probiotics, Metabolic Syndrome, Metagenomics, Immune HomeostasisAbstract
The gut microbiome — comprising trillions of bacteria, archaea, fungi, viruses, and protozoa — represents one of the most complex and physiologically important ecosystems in the human body. Recent metagenomics, metabolomics, and clinical studies have established the gut microbiome as a major regulator of immune homeostasis, metabolic physiology, neurological function, and host defence against pathogens. This review provides a comprehensive synthesis of the composition and functional characteristics of the gut microbiome, its bidirectional links with human health and key disease categories, and innovative therapeutics targeting the microbiome for clinical applications. Evidence demonstrates that microbial diversity and balance are critical to host health. Dysbiosis — microbial ecosystem imbalance — underlies the pathogenesis of inflammatory bowel disease, metabolic syndrome, type 2 diabetes, cardiovascular disease, neuropsychiatric disease, and multiple cancers. Gut-derived metabolites including short-chain fatty acids, bile acid derivatives, and tryptophan catabolites exert systemic effects through the immune, endocrine, and nervous systems. Evidence for therapeutic benefits of probiotics, prebiotics, synbiotics, dietary interventions, and fecal microbiota transplantation is growing. Standardized protocols, longitudinal studies, and precision microbiome medicine frameworks are essential to translate mechanistic insights into clinically validated applications.
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Copyright (c) 2026 Jeremy Mytskevych (Author)
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