Ginkgo leaf extract is sold for memory and circulation.
Calculator Official intake Study doses Best form Safety Sources
This is not an essential nutrient, so there is no official daily intake. Only study doses are shown.
These are doses tested in research, not personal advice. Some exceed the upper limit because they were short courses or given under medical care.
240 mg a day
The GEM trial gave 3,069 people aged 75 and over 120 mg twice a day or placebo for about 6 years. Ginkgo did not lower dementia or Alzheimer's rates, nor slow progression from mild cognitive impairment.
No best form
Why: Trials used standardised leaf extract; it still did not prevent dementia.
Not a normal food.
May raise bleeding risk with warfarin, aspirin and other antiplatelet drugs.
Use only standardised leaf extracts.
Pregnant, breastfeeding, on medication, or managing a health condition? Check with a doctor or pharmacist before starting a supplement.
Values checked: November 12, 2026.