Cistanche for Cognitive Function

Research suggests that Cistanche, both as an isolated extract and in combination with other herbs such as Ginkgo biloba, may support cognitive function and memory, with evidence spanning randomized controlled trials, systematic reviews, preclinical animal studies, and mechanistic laboratory research. The most clinically relevant human evidence includes two randomized controlled trials testing a Cistanche and Ginkgo biloba combination, both reporting improvements in memory and cognitive measures in healthy adults and older populations, and a 2025 network meta-analysis of 27 trials that ranked this combination highest for memory, executive function, and cognitive flexibility among 19 natural extracts. Preclinical studies propose several plausible mechanisms, including antioxidant activation via the Keap1-Nrf2-ARE pathway, gut microbiota modulation, blood-brain barrier preservation, and reduction of neuroinflammation and amyloid-beta accumulation, though these findings come primarily from mouse and rat models and have not been confirmed in humans. Overall limitations are notable: the human trials are few in number, relatively short in duration, and some involve multi-ingredient formulas that make it difficult to attribute effects to Cistanche alone, and a small open-label Alzheimer's trial from 2013 was inconclusive due to its lack of a placebo control and very small sample size, meaning the current evidence, while generally supportive in direction, remains preliminary and insufficient to draw firm conclusions.