Introduction and objective:
Every day, the human body is exposed to various stressors. Constant stress leads to a gradual weakening of the body, the disturbance of homeostasis and the emergence of somatic symptoms that require treatment. Due to chronic stress exposure, it seems important to support the body with natural supplementation, such as pre- pro- or synbiotics. The aim of the study was to review the latest reports from in vivo studies on the role of pre- pro- and synbiotics on the microbiota and the gut-brain axis (GBA) in stress exposure.

Review methods:
The article is an overview of literature reports from the past 5 years including in vivo studies examining the impact of pre- pro- and symbiotics on the gut microbiota and the GBA under stress conditions.

Abbreviated description of the state of knowledge:
Data from the World Health Organization (WHO) indicate that continuous exposure to stress contributes to up to 60% of chronic diseases. An important role in responding to stress is played by a properly functioning microbiome. Numerous studies concerning the pathology of the digestive system and disturbed microbiome show their relationship with nervous system disorders, thus confirming the importance of a proper bidirectional communication between these 2 systems.

Daily exposure to stress may disrupt the microbiota and proper functioning of the GBA. The cortisol released in response to stress is an essential physiological response that helps with coping in threatening situations. However, its release triggers a cascade of subsequent biochemical reactions dangerous to health, especially if they are triggered too often, i.e. under chronic stress. The latest scientific reports from in vivo studies clearly show that proper supplementation and diet (used with caution) can be a potential add-on therapy in the treatment of neuropsychiatric disorders.

This research was funded by the National Science Center, Poland, grant UMO-2019/35/N/NZ7/00982.
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