Gut microbiota and the role of probiotics in therapy

Thanks to rapid progress in the development and application of molecular techniques to the assessment of the human gut microbiome, the true nature, diversity and metabolic potential of this ‘hidden organ’ are being revealed. Simultaneously, the complex physiological, immunological and metabolic interactions between host and microbiome are being untangled. By contrast, the probiotic concept has been with us for decades and, while supported more by fad and folklore in the past, is now gaining support, not only from experimental work in animal models, but also by well-designed studies in human diseases, most notably infectious diarrheas, inflammatory bowel disease and the irritable bowel syndrome.

► The true diversity of the human gut microbiome is only beginning to be revealed.
► Commensals and thus probiotics interact with the host immune system in a number of different ways.
► The microbiota is a potent metabolic ‘organ’.
► A solid scientific basis for probiotic use has been established for a number of indications.
► Good evidence from clinical trials for probiotic use is more scanty but is beginning to emerge.