Effects of Ginseng on Cognitive Function: A Systematic Review and Meta-Analysis

Ginseng is a kind of traditional Chinese medicine. It is widely believed that ginseng can improve cognitive function, but its clinical efficacy is still controversial. This study aimed to systematically evaluate the effects of ginseng on cognitive function improvement. This is a systematic review and meta-analysis of the randomized controlled trials (RCTs). Searching PubMed, Web of Science, the Cochrane Library, and Medline databases to collect RCTs of ginseng on the effects of human cognitive function. The time range is from the establishment of the database to December 2023. The main intervention in the trials was ginseng preparation. The Cochrane risk-of-bias tool 2.0 (RoB2.0) and Jadad scale were used to assess the risk of bias and evaluate the quality of the included articles. After data extraction, meta-analysis was performed using Stata 17.0 software. A total of 15 RCTs were included, and 671 patients were analyzed. The subjects included healthy people, patients of cognitive impairment, schizophrenia, hospitalized, and Alzheimer's disease. The intervention measures were mainly ginseng preparations. The meta-analysis results indicated that ginseng has a significant effect on memory improvement (SMD = 0.19, 95%CI: 0.02-0.36, p < 0.05), especially at high doses (SMD = 0.33, 95%CI: 0.04-0.61, p < 0.05). Ginseng did not have a positive effect on overall cognition, attention, and executive function (SMD = 0.06, 95%CI: -0.64-0.77, p = 0.86; SMD = 0.06, 95%CI: -0.12 to 0.23, p = 0.54; SMD = -0.03, 95%CI: -0.28 to 0.21, p = 0.79). Ginseng has some positive effects on cognitive improvement, especially on memory improvement. But in the future, more high-quality studies are needed to determine the effects of ginseng on cognitive function. Trial Registration: Prospero: CRD42024514231.