Ginkgo biloba is one of the most studied medicinal plants in the world, and its popularity keeps growing in Morocco, where more and more people turn to it to support memory, concentration and blood circulation. Taken from a tree regarded as a true living fossil, this leaf extract holds a unique place in modern herbal medicine: it has been the subject of several hundred scientific publications and is among the best-selling dietary supplements in pharmacies and herbalist shops.
What does research actually say about its properties? What are its active compounds, how much should you take, and above all, when should you avoid it? This complete guide sets out the facts, without overblown promises.
What is ginkgo biloba?
Ginkgo biloba L. is a tree of the Ginkgoaceae family, the only surviving species of a botanical group that appeared more than 200 million years ago. That is why it is commonly nicknamed the “living fossil” or the “maidenhair tree”. Native to China, it is now planted all over the world, including as an ornamental tree along city avenues, because it tolerates pollution remarkably well.
Its leaves are instantly recognisable: fan-shaped, with a central notch that divides them into two lobes — hence the species name biloba. It is these leaves, not the seeds, that are harvested and turned into a standardised dry extract for use in herbal medicine.
One often-neglected point deserves emphasis: the raw leaf and the standardised extract are not equivalent. The preparations used in clinical trials are concentrated, purified extracts, obtained through a process that removes, among other things, ginkgolic acids, compounds that can trigger allergies. A simple infusion of dried leaves therefore offers neither the same concentration of active compounds nor the same safety profile.
Composition and active compounds
The reference extract, known by the code EGb 761, is the one on which the vast majority of studies have been based. It is standardised to two complementary families of molecules:
- Flavonoids (22 to 27%), expressed as flavone glycosides: quercetin, kaempferol, isorhamnetin. These are powerful antioxidants that help limit cellular oxidative stress.
- Terpene lactones (5 to 7%), divided between ginkgolides A, B and C (2.8 to 3.4%) and bilobalide (2.6 to 3.2%). These molecules are unique to ginkgo and are found in no other plant.
- Ginkgolic acids, limited to less than 5 ppm in pharmaceutical-grade extracts, precisely because they are irritating and allergenic in high doses.
Ginkgolides are studied in particular for their action on platelet-activating factor (PAF), a mediator involved in the aggregation of blood platelets. This property explains both ginkgo’s value for microcirculation and the precautions for use detailed below.
The benefits of ginkgo biloba
Traditional uses and the available clinical data converge mainly on cognitive and circulatory health. Here are the best-documented areas.
1. Memory and cognitive function
This is the plant’s historical indication. The leaf extract is traditionally used to support working memory, attention and information-processing speed, particularly in older people with mild cognitive decline. Clinical trial results remain mixed depending on the protocols and populations studied, but the highest doses (around 240 mg per day) and longer courses are the ones that have shown the most consistent effects.
2. Circulation and microcirculation
Ginkgo is traditionally used to promote blood flow through small vessels, especially in the brain and the extremities. This action is attributed to the combination of vessel-protecting flavonoids and anti-aggregating ginkgolides. In practice, it is often suggested to help with heavy legs, cold hands and feet, or tingling linked to sluggish peripheral circulation.
3. Tinnitus and dizziness
The standardised extract has long been used in Europe in the management of tinnitus and dizziness of vascular or vestibular origin. Experimental studies have shown improved vestibular compensation, meaning the brain’s ability to readjust after an inner-ear imbalance. Clinical data in humans nevertheless remain mixed, and any persistent tinnitus still calls for an ENT consultation.
4. Antioxidant protection
Its high flavonoid content gives the extract a measurable antioxidant activity, able to neutralise some free radicals. This mechanism probably underlies a large share of the effects observed on nerve tissue, which is particularly sensitive to oxidative stress because of its high oxygen consumption.
5. Eye comfort
A few small studies have looked at ginkgo’s effect on the retina, notably in age-related macular degeneration, with doses of 80 mg twice a day or 240 mg per day. The number of participants was very small (a few dozen), which does not allow firm conclusions: this avenue remains to be confirmed.
How to use it and dosage
The usual dose of the standardised extract is between 120 and 240 mg per day. Two dosing schedules are commonly used in the literature:
- 40 mg three times a day, with meals;
- or 80 mg twice a day, in the morning and at lunchtime.
A single daily dose of 120 mg is also possible with modified-release forms. It is generally advisable to start with the lowest dose for one to two weeks, then increase gradually if needed and if it is well tolerated.
A key point: ginkgo does not work immediately. Its effects on cognition and circulation build up slowly, and an honest assessment requires a course of at least 8 to 12 weeks. It is wise to take regular breaks rather than continuing month after month without interruption.
As for the form, choose a standardised leaf extract whose label explicitly states its flavonoid (24%) and terpene lactone (6%) content, as well as the limit on ginkgolic acids. Leaf tea, while pleasant, does not deliver comparable amounts of active compounds and cannot be considered equivalent.
Precautions and contraindications
This is the most important section, because ginkgo is an active plant, and an active plant is never harmless. Its effect on platelet aggregation calls for genuine vigilance.
Contraindications:
- Anticoagulant treatment (warfarin and similar drugs) or antiplatelet treatment, including low-dose aspirin;
- Known blood-clotting disorders, haemophilia;
- The period around surgery: stopping at least two weeks before a planned operation, including a tooth extraction, is recommended;
- Pregnancy and breastfeeding, due to a lack of sufficient safety data;
- Epilepsy or a history of seizures.
Special precautions: medical supervision is required for people with diabetes on insulin, people taking SSRI-type antidepressants, and in cases of unstable high blood pressure, where prolonged use may increase palpitations and blood-pressure fluctuations.
Possible side effects: they affect a minority of users and are most often mild and temporary — headaches at the start of a course, nausea, mild digestive upset, passing dizziness. If they persist, stop taking it.
Finally, never eat raw ginkgo seeds: they contain ginkgotoxin and pose a real risk of poisoning. Only the leaves are used in herbal medicine.
Frequently asked questions about ginkgo biloba
How long does ginkgo take to work?
There is no immediate effect. Any benefits for memory or circulation can be judged after several weeks of regular use, generally 8 to 12 weeks at the very least. Judging its effectiveness after a few days makes no sense.
Can you take ginkgo with aspirin?
No, not without medical advice. Combining an antiplatelet drug with ginkgo increases the risk of bleeding. The same caution applies to non-steroidal anti-inflammatory drugs taken over the long term.
Morning or evening: when is the best time?
It is best taken in the morning and at lunchtime, with meals, to improve digestive tolerance. Some people report a mild stimulating effect; in practice, it is better to avoid taking it late in the evening.
In summary
Ginkgo biloba is a well-documented plant extract whose value lies mainly in microcirculation and support for cognitive function. Its strength comes from its unique composition of ginkgolides and flavonoids; its main limitation comes from that very same activity, which makes it incompatible with blood-thinning treatments. Choose a standardised extract, stay within the range of 120 to 240 mg per day, commit to it over time, and talk to your doctor or pharmacist before you start, especially if you are already taking medication.
Further reading
- Ginkgo biloba — full botanical profile on Wikipedia
- Rosemary: benefits, dosage and precautions
- Sage: benefits, dosage and precautions
- Lemon balm: benefits, dosage and precautions
This article is provided for information purposes only and is in no way a substitute for medical advice. Ask your doctor or pharmacist for advice before starting a course, especially if you are already on treatment, pregnant or breastfeeding.
