Gut–brain axis and cognitive health in the elderly: Contemporary evidence and Ayurvedic perspectives

Abstract BACKGROUND: Cognitive impairment among the elderly is increasing worldwide, with over one-third of the geriatric population suffering from this condition in India alone. While research suggests that reducing pathogenic gut bacteria with probiotic supplementation can improve cognitive functions, diversified interventions are rare. We predicted that interventions that can create a healthy gut microbiota, as perceived in Ayurveda and present-day scientific literature, could positively impact the cognitive abilities of the elderly, and conducted a systematic search to examine the same. MATERIALS AND METHODS: A systematic search was conducted using databases like PubMed, Cochrane, and Directory of Open Access Journals to find studies published between 2000 and 2024 that discussed the effect of gut microbiota composition on cognitive functions among the elderly. We compared the search results with narratives from Ayurveda and recommended strategies to mitigate gut dysbiosis for enhanced cognition. RESULTS: We reviewed 51 research articles and found similarities between contemporary research and Ayurveda recommendations. Probiotic and prebiotic supplementations were mainly used for the enhancement of cognitive capabilities among the elderly. Some of these medications increased the presence of good gut bacteria, which overpowered pathogenic bacteria from the gut and improved the functioning of the gut–brain axis. A unique contribution from Ayurveda in this regard would be the step-wise process of administering Rasayana (~rejuvenation) therapy. CONCLUSION: Though Ayurveda medications and lifestyle interventions possess enormous scope in treating cognitive impairments, there is a need for scientific evidence through evidence-based studies to substantiate the therapeutic potential and to formulate measures to prevent the onset of cognitive impairments.