Alzheimers Home > Ginkgo Biloba Extract Information
Researchers at the New York Institute for Medical Research in Tarrytown, New York conducted the first clinical study of ginkgo biloba extract and dementia in the United States. Their findings were published in the Journal of the American Medical Association (October 22/29, 1997). These scientists examined how taking 120 mg a day of a ginkgo biloba extract affected the rate of cognitive decline in people with mild to moderately severe dementia due to Alzheimer's disease and vascular dementia. At the end of the study, they reported a small treatment difference in people given the ginkgo biloba extract.
Three tests were used to measure changes in the condition of participants. First, participants showed a slight improvement on a test that measured their cognitive function (mental processes of knowing, thinking, and learning). Second, participants showed a slight improvement on a test that measured social behavior and mood changes that were observed by their caregivers. Third, participants showed no improvement on a doctor's assessment of change test.
Because 60 percent of the people did not complete the study, findings are difficult to interpret and may even be distorted. In addition, this study did not address the effect of ginkgo biloba extract on delaying or preventing the onset of Alzheimer's disease or vascular dementia. The researchers recommend more investigation to determine if these findings are valid, understand how ginkgo biloba extract works on brain cells, and identify an effective dosage and potential side effects.
The National Institute on Aging (NIA) and the Office of Alternative Medicine, both at the National Institutes of Health, are funding a small study to test the effectiveness of ginkgo biloba extract in treating Alzheimer's disease. This two-year study at the Oregon Health Sciences University in Portland started in 1997. It will include 42 patients with mild to moderate Alzheimer's disease.