Ginkgo Biloba Does Not Prevent Alzheimer's Disease
Ginkgo Biloba is the latest supplement shown in randomized clinical trials to be of no benefit in the prevention of dementia or Alzheimer’s disease. Long thought to be of use in the preservation of memory, Ginkgo biloba has worldwide sales of $249 million annually. Now a new trial published in the Journal of the American Medical Association shows Ginkgo is of no benefit.
The Ginkgo study looked at 2587 seniors over age 75 with normal cognition at baseline and they were assessed every 6 months for dementia. After 6.1 years, 523 patients were diagnosed with dementia, but there was no difference between the Ginkgo Biloba group and the placebo group. Ninety-two percent of the dementia patients were diagnosed with Alzheimer’s disease.
The seniors that received Gingko took 120mg twice daily and the control group took placebo tablets twice daily. The rate of Alzheimer’s disease did not differ and the authors concluded that 240mg of Gingko Biloba, taken daily for 6 years, was not effective in reducing the incidence of dementia in elderly patients.
This trial was the largest and longest non-industry-funded, placebo-controlled trial to ever look at Ginkgo and preservation of memory. Dr. Lon Schneider, University of Southern California states, “Users of this extract should not expect it to be helpful. Moreover, the potential adverse effects of G. biloba extract illustrate why it is untenable to recommend a drug or nutraceutical in the absence of efficacy evidence simply because it could possibly help and initially appears harmless.”
Dr. Steven T. DeKosky, the principal investigator said, “We were disappointed. We were hopeful this would work.” He went on to say “At this point in time, I wouldn’t tell anybody to take the medication in hopes that it would work to prevent Alzheimer’s.
Alzheimer’s has no cure and no known prevention. It causes slow progression of memory loss leading to severe brain damage and death.
Other supplements that have been proven non-effective for prevention of stroke or cardiovascular disease are Vitamin E and Vitamin C. A second analysis that looked at cancer also showed no benefit for either vitamin.
Reference about Alzheimer's Disease - Alzheimer's Association.