Ginkgo biloba

The VerdictLOW CONVICTION

The biggest trials ever run gave ginkgo to thousands of people for years and it did nothing for memory.

If you take ginkgo for memory or focus, stop. The two largest independent trials gave it to thousands of older adults for years and it didn't beat a sugar pill. Ask yourself one screening question: do you have a dementia diagnosis being managed by a clinician? If no, save your money.

What the data actually shows: in the two biggest independent trials (about 3,000 and 2,800 people, run for 5-6 years), ginkgo did not prevent dementia or slow memory decline, and it did nothing for healthy adults either.
What most people get wrong: the "clinically studied" claim comes from trials in people who already have dementia, using one specific German extract, not from healthy people on a generic capsule.
What to watch for: ginkgo genuinely thins your blood, so it's risky with aspirin, fish oil, or anticoagulants, and you should stop it 1-2 weeks before any surgery.

Ginkgo's selling point is that it thins the blood a little and nudges circulation, on the theory that more blood flow means a sharper brain. But "more blood flow therefore better memory" is a guess, and it was tested directly in thousands of people over years. The blood-thinning is real. The memory boost never showed up.

That's the general answer. Your stack is different.

Check your whole stack

If you take ginkgo for memory or focus, stop. Ask yourself: do you have a dementia diagnosis a clinician is treating? If no, save your money.

The two largest independent trials gave thousands of older adults ginkgo for years and it didn't beat a placebo for memory or dementia prevention.

Takes less than 2 minutes. One bottle off your shelf.

The Protocol

What to take, if anything

Who	Dose	Form	Timing
Healthy adults (memory/focus)	No effective dose	—	Don't bother
Diagnosed dementia (clinician-led)	240 mg/day	EGb 761 only	Daily with food; judge at 22 weeks
Mild cognitive impairment	Not established	EGb 761	Weak signal at best
Intermittent claudication (leg pain)	120-160 mg/day	Standardized extract	Superseded by exercise/medication

Forms

EGb 761

Standardized 24% / 6%

The only form with a real evidence base. Sold as Tebonin, Tanakan, Rökan.

~£15-30/month

Generic "24/6"

Often below label

Independent testing repeatedly finds low active content and cheap-flavonoid spiking. Not reliably the same thing.

~£5-12/month

Whole-leaf / tea

Low, erratic

No standardization, higher contaminant risk. Avoid.

Low

Absorption tip: Take with food. The fraction that matters is the terpene lactones, and that's exactly what cheap products skimp on, so form and third-party verification matter far more than timing. There's no "absorption hack" that rescues a low-quality extract.

Safety & Interactions

Take this, watch for this

Warfarin & DOACs (blood thinners)

Increased bleeding risk, with hemorrhage case reports. Avoid.

Aspirin & clopidogrel (antiplatelets)

Additive platelet inhibition. Avoid.

NSAIDs (ibuprofen, naproxen) & high-dose fish oil

Additive bleeding risk. Monitor or avoid.

Surgery & dental procedures

Stop ginkgo at least 1 to 2 weeks before any procedure.

Seizure disorders

Ginkgotoxin may lower the seizure threshold. Avoid if you have a seizure disorder. Never eat raw ginkgo seeds (genuinely toxic).

Who should not take it

Anyone on anticoagulants or antiplatelets: real bleeding risk for no offsetting benefit.
Pre-surgical or pre-dental patients: stop 1-2 weeks ahead.
People with bleeding disorders.
People with seizure disorders.
Pregnancy and breastfeeding: insufficient safety data, avoid.

Upper limit: No formal safe ceiling is established; 240 mg/day of EGb 761 is the tested dose, not a defined safety threshold. Side effects at standard doses are mild and near placebo (occasional GI upset, headache, dizziness). The bleeding interactions are the real story.

Conviction

LOW

For healthy adults, the memory and prevention claims are debunked by the two largest independent trials. The only real signal is modest, leans heavily on the extract's manufacturer, and lives inside diagnosed dementia under clinician care.

What would change this verdict?

An independent (non-manufacturer-funded), placebo-controlled trial of 300+ healthy adults aged 50-70 with no dementia, using a third-party-verified standardized extract at 240 mg/day for a year or more, with a pre-registered objective memory endpoint, showing a real benefit, would move healthy-adult cognition from debunked to low. A large independent replication of the behavioral-symptom signal in diagnosed dementia would raise that one indication to moderate. A biomarker-based trial in mild cognitive impairment is currently enrolling and could shift that verdict either way.

Worth Your Money?

Weekly costRoughly £4-7 per week for real EGb 761; less for generics that may not match it.

Worth it ifA clinician is managing a dementia diagnosis and has chosen it as an add-on. That's essentially the only case.

Lower priority ifYou're healthy and want sharper thinking. Your next £20 does more on sleep, training, or protein than on a supplement that failed its biggest trials.

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Sources

Key references

DeKosky ST, et al. (2008). Ginkgo biloba for prevention of dementia (GEM Study). JAMA. RCT, N=3,069, EGb 761 240 mg/day median 6.1y. No reduction in dementia incidence.
Snitz BE, et al. (2009). Ginkgo biloba for preventing cognitive decline (GEM). JAMA. RCT, N=3,069. No slowing of cognitive decline.
Vellas B, et al. (2012). Standardised ginkgo extract for prevention of Alzheimer's (GuidAge). Lancet Neurology. RCT, N=2,854, 5y. No reduction in AD conversion.
Solomon PR, et al. (2002). Ginkgo for memory enhancement: RCT. JAMA. N=230 healthy older adults. No benefit.
Gauthier S, Schlaefke S (2014). EGb 761 in dementia: SR & MA. Clin Interv Aging (PMID 25506211). 9 RCTs. Favorable at 240 mg/day. Schwabe-affiliated.
Weinmann S, et al. (2010). Ginkgo in dementia: SR & MA. BMC Geriatrics (PMID 20236541). Small, inconsistent benefit. Independent.
Tan MS, et al. (2015). Ginkgo for cognitive impairment and dementia: SR & MA. J Alzheimers Dis (PMID 25114079). 240 mg/day helped in dementia, weak in MCI.
Savaskan E, et al. (2018). EGb 761 on behavioral symptoms of dementia: MA. Int Psychogeriatr (PMID 28931444). Significant symptom reduction. Schwabe-affiliated.
Spiegel R, et al. (2018). EGb 761 on tinnitus/dizziness in dementia: MA. Clin Interv Aging (PMID 29942120).
Pittler MH, Ernst E (2000). Ginkgo for intermittent claudication: MA. Am J Med (PMID 11014719). +34m walking distance.
Tsai TY, et al. (2018). Ginkgo for acute mountain sickness: SR & MA. BMJ Open (PMID 30121603). High heterogeneity, inconsistent.