Abstract
It is estimated that the intestine of an adult human hosts 10–100 trillion microorganisms of between 500 and 1,000 different species, collectively referred to as the microbiome. However, the composition and dynamics of this «normal» microbiome remain incompletely defined. Each individual's microbial community exhibits a unique pattern at the species level. Objective of the study: To investigate the effects of probiotics and prebiotics to the composition of gut microbiota in healthy individuals based on current data. Methods: A review of literature sources devoted to this topic was carried out, data of publications in Pubmed, Web of Science, Scopus databases for the last ten years were analysed using the keywords: «human microbiome», «diet», «prebiotics» and «probiotics». The microbiome represents the genes of the microbiota, where the number of bacterial genes (constituting the vast majority of the microbiota) actually exceeds the number of human genes by 150 times. A prebiotic is a non-digestible food ingredient that beneficially affects the host organism by selectively stimulating the growth and/or activity of a certain number of bacteria in the colon. For a food ingredient to be classified as a prebiotic, it must not be hydrolyzed or absorbed in the upper gastrointestinal tract; it must be a selective substrate for a number of beneficial bacteria; it must be capable of altering the colonic flora toward a healthier composition; and it must induce a systemic effect beneficial to the host's health. Conclusions: The literature review conducted showed that dietary supplements in the form of pro and prebiotics are generally safe for most people and can be used effectively to support gut health. Bifidobacteria and fructoligosaccharide supplementation were found to alter the composition of the gut microbiota, reducing Bacteroides, Clostridia and Fusobacterium from 25% to 4%. However, further clinical studies are needed to investigate the effects of specific nutritional support components on the microbiota, especially in the long term.