Question

My nutritionist has recommended that I take a plant supplement called ginkgo biloba, which she says will help with my memory and concentration problems. Do you know anything about this treatment? Is there any evidence that it helps people with ME? And is it safe?

Answer

Ginkgo biloba is extracted from the dried leaves of a tree that originated in China. The plant extract has been used in Chinese medicine for over 2,000 years – where it is claimed to improve memory and intellectual function. It is also claimed to help asthma, bronchitis and blood-circulation problems.

More recently, Gingko biloba has been used in Germany to treat ‘cerebral insufficiency' – a controversial diagnosis that appears to cover tiredness and decreased physical performance as well as problems with memory and concentration.

As far as hard science is concerned, the leaves contain pharmacologically-active ingredients called flavonoids, ginkolides and terpenoids – which are claimed to increase cerebral (brain artery) blood flow and inhibit platelet aggregation (which would normally help to stop bleeding).

At a cellular level there is some evidence to show that it can protect neurons (nerve cells) from damage caused by a variety of factors. So there is some very limited theoretical basis to its use.

A number of clinical trials have been conducted in people with dementia and Alzheimer's disease to see if it can improve mental functioning. However, there is no sound evidence from clinical trials to show benefit when compared to a placebo. There have not been any proper clinical trials involving people with ME/CFS.

As far as safety is concerned, there appears to be a fairly low incidence of side-effects. More commonly reported side-effects include allergy, anxiety and restlessness, nausea, headaches, stomach upsets and sleep disturbance.

Gingko can cause bleeding problems due to the effect on platelets – so it should be avoided if you have any sort of pre-existing bleeding disorder or are taking anticoagulants (bloodthinning drugs). Caution is also advised in people with high blood pressure and those taking MAOI antidepressants. It is best avoided in pregnancy.

The extract is available in tablet or capsule form – the usual dose being 120 to 240mg of extract per day. It is widely available in pharmacies and health supplement shops. It is not available on NHS prescription.

In conclusion, there are some theoretical reasons why Gingko might improve mental function but no sound evidence from clinical trials to show that it can help to improve cognitive dysfunction in ME/CFS or any other health condition.

More Information:

• Information on Gingko Biloba from the US National Institutes of Health.
• MEA information booklet covering the management of cognitive dysfunction in both ME/CFS and Long Covid.
• Please let us know if you have any experience of using Ginkgo biloba. Please email caroline.cavey@meassociation.org.uk