Ginkgo Biloba
The NIH-funded GEM trial (DeKosky 2008, n=3,069, 240mg/day, median 6.1 years) found no reduction in dementia or Alzheimer's incidence in people aged 75+. For existing cognitive impairment and dementia, a meta-analysis of 9 RCTs (Tan et al., 2015, 22–26 weeks, mainly 240mg/day EGb 761) found benefits on cognition and daily living, concentrated in patients with neuropsychiatric symptoms. The 2026 Cochrane review of 82 RCTs found small-to-moderate benefits in dementia (low-certainty evidence) but little or no effect in mild cognitive impairment. A 2013 review rated the dementia evidence low quality, noting most trials were pharmaceutical-industry sponsored. Ginkgo raises bleeding risk with warfarin.
Evidence reviewed:
Mechanism of action
Ginkgo Biloba extract (standardised to 24% ginkgo flavone glycosides and 6% terpene lactones) works primarily by improving cerebral blood flow through vasodilation and platelet-activating factor (PAF) inhibition. The terpene lactones (ginkgolides A, B, C and bilobalide) reduce blood viscosity and improve microcirculation in brain capillaries. Additionally, ginkgo has antioxidant properties that protect neuronal membranes from lipid peroxidation.
Clinical evidence summary
The NIH-funded GEM trial (DeKosky 2008, n=3,069, 240mg/day, median 6.1 years) found no reduction in dementia or Alzheimer's incidence in people aged 75+. For existing cognitive impairment and dementia, a meta-analysis of 9 RCTs (Tan et al., 2015, 22–26 weeks, mainly 240mg/day EGb 761) found benefits on cognition and daily living, concentrated in patients with neuropsychiatric symptoms. The 2026 Cochrane review of 82 RCTs found small-to-moderate benefits in dementia (low-certainty evidence) but little or no effect in mild cognitive impairment. A 2013 review rated the dementia evidence low quality, noting most trials were pharmaceutical-industry sponsored. Ginkgo raises bleeding risk with warfarin.
Human effect matrix
Based on human clinical trials only. Animal and in-vitro data excluded.
| Effect | Evidence | Magnitude | Studies |
|---|---|---|---|
| Cerebral Blood Flow | strong | Moderate | — |
| Memory (Cognitive Decline) | moderate | Moderate | 3 |
| Memory (Healthy Adults) | mixed | Small | — |
| Dementia Prevention | strong | Negligible | 1 |
Evidence key: Strong = multiple consistent RCTs · Moderate = smaller/fewer RCTs · Preliminary = early trials or small n · Mixed = conflicting results
Documented benefits
- Cognition and daily living in dementia (low-certainty evidence)
- Improved cerebral blood flow (not re-verified in our 2026 review)
- Antioxidant activity
Side effects & cautions
- Headache
- GI discomfort
- Increased bleeding risk with blood thinners: in a large Veterans Administration cohort, ginkgo plus warfarin raised bleeding risk (HR 1.38), and a systematic review links ginkgo to major bleeds including intracranial bleeding — avoid with anticoagulants
- Rare: allergic skin reactions
How to take
Stacking recommendations
Ingredients that pair well with Ginkgo Biloba and why.
Ginkgo improves blood delivery while PS supports membrane function — complementary pathways for age-related cognitive support.
Ginkgo provides acute blood flow support; Lion's Mane builds long-term neuroprotection via NGF. Addresses both immediate and structural brain health.
Both have long-term memory benefits via different mechanisms. Ginkgo via blood flow; Bacopa via synaptic density. Combined for comprehensive memory support in older adults.
Frequently asked questions
Does Ginkgo Biloba actually work for healthy young adults?
The evidence is mixed. The clearest benefits are in people with dementia, and the 2026 Cochrane review found little or no effect even in mild cognitive impairment. In healthy young adults, effects on memory and attention are inconsistent across trials. If you are under 40 and cognitively healthy, L-theanine + caffeine has stronger acute evidence.
What is EGb 761 and why does it matter?
EGb 761 is a specific pharmaceutical-grade Ginkgo biloba extract manufactured by Dr. Willmar Schwabe Pharmaceuticals. It is standardised to 24% ginkgo flavone glycosides and 6% terpene lactones, with toxic ginkgolic acid removed below 5ppm. It is the extract used in the trials pooled by the meta-analysis we cite (Tan 2015). Generic ginkgo products may not match the potency or purity.
Can I take Ginkgo with blood thinners?
Avoid it unless your doctor agrees. In a large Veterans Administration cohort, taking ginkgo with warfarin raised bleeding risk by 38% (HR 1.38), and a systematic review of warfarin interactions links ginkgo to major bleeding events, including intracranial bleeding. The interaction is clinically documented and potentially serious.
How long before I see results?
The positive dementia trials ran 22–26 weeks at 240mg/day, and the Cochrane review assessed outcomes at 6 months. Do not judge efficacy at 1–2 weeks.
Ginkgo Biloba in Japan
Products in Japan
None of the stacks we have audited are listed in our catalogue in Japan yet.
Consumer Affairs Agency (FFC)
Regulatory note
本ページは教育目的の編集コンテンツであり、医学的助言を構成するものではありません。日本国内で販売される機能性表示食品（FFC）および特定保健用食品（FOSHU）は、消費者庁への届出または許可を必要とします。届出のない輸入品については、日本の薬機法（旧薬事法）の下で疾病治療を示唆する表現は規制されます。サプリメントを開始する前に、必ず資格のある医療専門家にご相談ください。This page is editorial and not medical advice. Foods with Function Claims (FFC) and Foods for Specified Health Uses (FOSHU) sold in Japan require notification or approval from the Consumer Affairs Agency. Imported products without notification cannot make disease-treatment claims under the Pharmaceuticals and Medical Devices (PMD) Act. Consult a qualified healthcare professional before starting any supplement.
Sources (6)expand
- PMID 19017911Ginkgo biloba for prevention of dementia: a randomized controlled trial. (2008)
- PMID 25114079Efficacy and adverse effects of ginkgo biloba for cognitive impairment and dementia: a systematic review and meta-analysis. (2015)
- PMID 41641880Ginkgo biloba for cognitive impairment and dementia. (2026)
- PMID 24991128Ginkgo biloba extract for dementia: a systematic review. (2013)
- PMID 26958257Ginkgo and Warfarin Interaction in a Large Veterans Administration Population. (2015)
- PMID 32478963Warfarin and food, herbal or dietary supplement interactions: A systematic review. (2020)