Creatine supplementation and cognitive aging: The challenge of crossing the blood–brain barrier

Background: Creatine supplementation has been widely studied for muscle health and aging. Recently, its possible effects on brain function and cognition in older adults have drawn attention, though consistent clinical evidence remains limited. Aim: To discuss current challenges and limitations regarding creatine supplementation as a strategy for cognitive improvement in older adults. Methods: Not applicable (commentary article, no original methods involved). Summary: A key uncertainty is whether supplemented creatine crosses the blood–brain barrier in sufficient amounts to affect neuronal metabolism. Although some studies show modest brain creatine increases, methodological constraints, individual variability, and the absence of standardized protocols limit firm conclusions. Assertions of cognitive enhancement based solely on supplementation risk overstating available data. This commentary highlights physiological and methodological barriers and calls for rigorous trials using advanced imaging, standardized dosing, and integration with lifestyle interventions. Until such evidence is available, creatine supplementation for cognition in older adults should be considered a hypothesis rather than an established clinical practice.