Abstract
Background: Gut microbiota directly influences brain function and emotional state through gut-brain axis. Its imbalance is associated with mental disorders, while bacteria such as Lactobacillus and Bifidobacterium could have neuroprotective effects. The aim of this research was to analyze the available scientific evidence on the relationship between the gut microbiota and mental disorders, as well as to evaluate the impact of natural dietary components on the modulation of this microbiota as a preventive and therapeutic strategy. Methods: A systematic review of studies that analyzed how the gut microbiota influences mental disorders such as anxiety and depression was conducted, highlighting the role of the gut-brain axis in emotional regulation. Through a thorough search and methodological support of the PRISMA strategy, studies were selected that evaluated the impact of natural dietary components as a preventive and therapeutic strategy. Results: In the initial stage review, 1419 records were identified from three widely recognized scientific databases in the field of health and nutrition: PubMed, Web of Science and ScienceDirect. and after applying inclusion criteria focused on the topic, 15 randomized clinical trials were selected, which provide key evidence on the contribution of the Microbiota to health. Conclusions: Intestinal dysbiosis appears as a relevant factor in the pathophysiology of these conditions, mediating neuroinflammatory processes, alterations in the gut-brain axis and imbalances in key neurotransmitters. In this context, natural dietary components -such as probiotics, prebiotics and specific nutritional interventions- emerge as promising strategies to modulate the gut microbiota and, thereby, contribute to the prevention and treatment of mental disorders.
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