Pre-clinical and human clinical trial data reveal exciting potential for novel treatment targets and therapeutic modulation with prebiotics, medicinal herbs, probiotics, and synbiotics in health, aging, and neurodegeneration and are reviewed here. While greater insights and characterization of the microbiota-gut-brain axis have been revealed over the past decade, salient questions related to the pathology, pathogenesis and clinical treatment of the axis in the context of both health and neurodegenerative disease remain and are discussed in this review CLICK TO REVIEW