Introduction and objective:
For many years gut microbiota has been an object of interest to scientists. Over the years there have appeared an increasing number of surprising discoveries about the function of gut microbiota and its impact on the human body. These once underestimated prokaryotic organisms, perform a number of functions for a host, including the regulation of metabolism, immunity and the nervous system. The aim of the review was to summarize evidence-based knowledge and the most important health aspects of microbiota relying on the current literature, to emphasize the holistic influence on health, well-being and ageing.

Review methods:
The presented article is a review of current literature concerning the impact of the gut microbiota on human body, carried out based on an English language search of bibliographic database PubMed. The following key words and their combinations were used: ‘microbiota’, ‘diet and microbiota’, ‘gut-brain axis’,’microbiota transplantation’, ‘autoimmune diseases-microbiota’, and ‘ageing and microbiota’.

Abbreviated description of the state of knowledge:
Nowadays it is known that gut microbiota can synthesize not only vitamins, which has been discovered nearly 60 years ago, but being a part of the gut-brain axis, can also synthesize neurotransmitters, and have a direct effect on our behaviour and well-being. It is also known, that the disturbance within the composition or the function of microbiota contributes to morbidity.

The role of gut microbiota seems to be greater than has been assumed to-date. Proper diet, everyday physical activity and avoidance of unnecessary antibiotic therapy contribute to the balance of microbiome. Care should be taken of gut microbiota, and the measurable health benefits would be perceived on multiple levels.

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