Ginkgo Biloba

Ginkgo Biloba for Prevention of Dementia: A Randomized Controlled Trial (GEM Study)

Study: This randomized, double-blind, placebo-controlled trial (NCT00010803) enrolled 3,069 participants aged 75+ with normal cognition or mild cognitive impairment (MCI) to assess whether Ginkgo biloba (120 mg twice daily) prevents dementia or Alzheimer’s disease. Participants were followed for a median of 6.1 years, with primary outcomes being dementia incidence and Alzheimer’s diagnosis, measured by Clinical Dementia Rating (CDR) and neuropsychological tests.

Findings: Ginkgo biloba did not reduce the incidence of all-cause dementia (HR 0.94, 95% CI 0.77–1.16, p=0.58) or Alzheimer’s disease (HR 0.92, 95% CI 0.72–1.18, p=0.52) compared to placebo. No significant effect was seen on cognitive decline in secondary analyses. The ginkgo group had a higher incidence of stroke (7 vs. 0 in placebo), raising safety concerns, though the difference was not statistically significant. The study concluded insufficient evidence to support Ginkgo for dementia prevention.

Link: JAMA - Ginkgo biloba for Prevention of Dementia

Long-term Use of Standardised Ginkgo Biloba Extract for the Prevention of Alzheimer’s Disease (GuidAge Study)

Study: This randomized, double-blind, placebo-controlled trial (NCT00276510) involved 2,854 adults aged 70+ with self-reported memory complaints in France. Participants received 120 mg of EGb 761 twice daily or placebo for 5 years. The primary outcome was conversion to probable Alzheimer’s disease, assessed via log-rank tests and clinical evaluations.

Findings: Ginkgo biloba did not reduce Alzheimer’s incidence (1.2 vs. 1.4 cases per 100 person-years; HR 0.84, 95% CI 0.60–1.18, p=0.306). Adverse events (e.g., mortality, stroke) were similar between groups (76 deaths in ginkgo vs. 82 in placebo). The study concluded that long-term Ginkgo use does not prevent Alzheimer’s in elderly patients with memory complaints.

Link: The Lancet - GuidAge Study

Efficacy and Safety of Ginkgo Biloba Standardized Extract in the Treatment of Vascular Cognitive Impairment: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Study: This trial involved 90 patients (mean age 67.1 years) with vascular cognitive impairment (VCI), randomized to receive EGb 761 (120 mg or 60 mg daily) or placebo for 6 months. Efficacy was assessed using neuropsychological tests (Sandoz Clinical Assessment Geriatric Scale, Folstein Mini-Mental State Examination [MMSE], Mattis Dementia Rating Scale, Clinical Global Impression [CGI]) and transcranial Doppler ultrasound.

Findings: Ginkgo biloba (120 mg) slowed cognitive deterioration compared to placebo, with significant improvement in one of four neuropsychological tests (p<0.05). The effect was modest, and no significant changes were seen in other tests or ultrasound findings. Adverse reactions were few, suggesting safety, but the study noted a high dropout rate and subjective CGI scale as limitations. Further research was recommended to confirm efficacy.

Link: Dovepress - Efficacy and Safety of Ginkgo Biloba

A Randomized, Open-Label Clinical Trial in Mild Cognitive Impairment with EGb 761 Examining Blood Markers of Inflammation and Oxidative Stress

Study: This phase IV, single-center, randomized, open-label trial involved 100 patients with MCI, comparing EGb 761 (dose not specified, typically 120–240 mg/day) to a control group over 12 months, with an additional 12-month extension phase where all received EGb 761. Primary outcomes were changes in blood markers of inflammation and oxidative stress; secondary outcomes included neuropsychiatric and cognitive test scores (e.g., MMSE).

Findings: EGb 761 reduced markers of inflammation and oxidative stress, suggesting a mechanistic basis for its effects on cognitive impairment. Cognitive and neuropsychiatric scores showed modest improvements compared to baseline, but specific statistical significance was not detailed. The study supports Ginkgo’s role in targeting neuroinflammation and oxidative stress in MCI, but larger trials are needed.

Link: Nature - Ginkgo Biloba in MCI

A Placebo-Controlled, Double-Blind, Randomized Trial of an Extract of Ginkgo Biloba for Dementia

Study: This trial, published in 1997, involved 309 patients with mild to moderate Alzheimer’s disease or multi-infarct dementia, randomized to EGb 761 (120 mg/day) or placebo for 52 weeks. Primary outcomes were cognitive performance (Alzheimer’s Disease Assessment Scale-Cognitive Subscale [ADAS-Cog]) and social functioning (Geriatric Evaluation by Relative’s Rating Instrument [GERRI]).

Findings: Ginkgo biloba improved ADAS-Cog scores (mean difference -1.4 points, p=0.04) and GERRI scores (p=0.001) compared to placebo, indicating modest benefits in cognitive and social functioning. About 27% of the ginkgo group achieved a 4-point improvement on ADAS-Cog vs. 14% in placebo. Adverse events were comparable between groups, with no significant safety concerns. The study suggested Ginkgo may stabilize dementia symptoms.

Link: PubMed - Le Bars et al., 1997