Abstract
Sleep is essential for physical, mental, and emotional well-being, regulating processes such as memory consolidation, hormonal balance, and immune function. It is influenced by the gut-brain axis, which integrates signals from the gut microbiome and the central nervous system. The aim of this review was to investigate the relationship between the gut microbiome and sleep quality in adults, identifying the main mechanisms of bidirectional communication and associated therapeutic strategies. The methodology consisted of a qualitative and descriptive literature review, with a search for articles in the PubMed database between 2020 and 2025. The results showed that, collectively, the findings reinforce that the gut microbiota plays a central role in sleep regulation. Probiotic supplementation improves sleep quality, reduces anxiety and depressive symptoms, and modulates metabolic pathways related to neurotransmission, while low microbial diversity and dysbiosis are associated with poorer sleep quality. It is concluded that the gut microbiota acts as a central modulator of sleep in adults, and interventions targeting its modulation represent a promising strategy for promoting healthy sleep and well-being, standing out as a relevant field for future clinical and nutraceutical research.