Background/Objectives: The human gastrointestinal tract is a dynamic and interactive micro-ecosystem, with its distinct microbial population residing in the gut. The healthy condition of the gut is integrated into the normal functioning of all physiological activities. The gut microbiome is critical for the functioning of metabolism via several gut-axis connections with different systems in the human body; thus, it affects the status of health and general well-being. The fundamental physiology and homeostatic shifts are associated with specific diseases caused by a disrupted balance in the diversity of the gut microbiome, which could be due to a condition of dysbiosis in a host, instigated by several reasons. Some studies have been conducted on the selective isolation of probiotic species from dairy and other food sources to obtain effective probiotic strains, which have been studied and used by dietary intake strategies to restore gut microbial diversity, which is disturbed by some disease/s. Methods: Our search strategy included specific keywords—gut, microbiota, microbiome, disease, dysbiosis, probiotic bacteria and yeast—and was based on a timeframe of 15 years in the web-based electronic databases of PubMed, Scopus, and Web of Science. Among the few hundred results, a secondary screening was conducted to select references on probiotics studied for disease management with preclinical evidence and some reports on clinically validated outcomes; we excluded the search results for screening fermented foods for taxonomy studies of isolated probiotics. Results: The summarised information using two figures and two tables has been presented in this article from the review of 137 selected references: >75% have been published in the last 10 years. Conclusions: Further advances in modelling and analysis of the gut microbiota are required to understand their influence on the occurrence of certain diseases; this approach will allow us to establish research strategies for filling knowledge gaps, inconsistencies in clinical evidence, or limitations in translating probiotic effects from experimental models to humans.
Dahiya et al. (Tue,) studied this question.