Oct 21, 2002
By Richard Woodman
Britain's Alzheimer's Society said on Monday that a major review of clinical trials provides "promising evidence" that the dietary supplement Ginkgo biloba can improve memory and function in people with dementia.
The extract from the leaves of the Chinese Ginkgo tree is widely advertised for a variety of conditions including memory loss but scientific evidence has often been conflicting.
The Society said researchers at the Cochrane Collaboration in Oxford had reviewed 33 clinical trials and concluded that the remedy appeared to be safe with no excessive side effects.
"Many of the early trials used unsatisfactory methods, were small, and we cannot exclude publication bias. But overall there is promising evidence of improvement in cognition and function associated with Ginkgo," it said in a statement.
It announced that a large placebo-controlled study of 400 people with dementia would now be carried out by Imperial College and the Royal London Homeopathic Hospital to find out the size and mechanism of the treatment effects.
"Ginkgo contains a number of organic biologically active components," said Dr. Peter Fisher, Director of Research at the Royal London Homeopathic Hospital. "It is the ginkgolides that are unique to the Ginkgo tree, although it is not fully known which component or components are the ones that give the leaves their medicinal properties."
Dr. James Warner, senior lecturer and consultant in geriatric psychiatry at Imperial College London, said: "The medicinal effects of Ginkgo are believed to be gained by causing blood vessels to dilate, improving blood flow to the brain, and through thinning the blood and making it less likely to clot.
"Ginkgo probably also has some anti-oxidant effects, protecting nerve
cells against biological 'rusting,'" he continued. "All of these effects
would suggest that Ginkgo might slow down a degenerative process."
© 2002 Reuters Ltd