Prebiotic Intake in Older Adults: Effects on Brain Function and Behavior.

PURPOSE OF REVIEW: This literature review summarizes the evidence for and against the impact of prebiotics on brain function and behavior in older adults.

RECENT FINDINGS: Current evidence generally supports the intake of prebiotics to increase beneficial gut bacteria concentrations. These bacteria appear to impact endocrine, immunologic, and neuronal communication along the gut-brain axis to alter brain function and behavior. Preliminary evidence in human studies consistently support prebiotics doses of ~ 5-10 g/d as safe to improve brain function (i.e., learning and working memory) and behavior (i.e., anxiety and mood). However, these studies are mainly of short duration (4-12 weeks) and limited to healthy, young, and middle-aged adults. More research is needed to identify a safe and effective dose, duration, and delivery method, particularly among diseased, older adults.