Unclear Findings for Ginkgo in Alzheimer's Prevention
Over the years, most research has found that ginkgo can effectively improve memory and thinking funtion, however, not all studies have found positive results
Ginkgo biloba is one of the most widely used medicinal herbs in the world. Over the years, most research has found that it can effectively improve memory and thinking (cognitive) function and slow the progression of Alzehimer's disease in older people. Not all studies have found these positive effects, however, including a new study with unclear results. In this study, seniors with early signs of memory loss and assigned to take ginkgo were 16% less likely to go on to develop Alzheimer's disease, compared with people assigned to a placebo. However, this difference was not statistically significant, leaving the potential benefits of ginkgo in question.
Giving ginkgo to elders with memory loss
The study, published in Lancet Neurology, included 2,854 people over 70 who told their doctor they were having memory problems. About half of them were assigned to take 120 mg of ginkgo twice daily and the other half were assigned to take a placebo. They were monitored for changes in memory and cognitive function as well as new diagnoses of dementia and probable Alzheimer's disease for five years.
Ginkgo showed no clear protective effect
Overall, there was no statistically significant difference in the incidence of Alzheimer's disease between people in the ginkgo and placebo groups.
However, results were more mixed when the researchers looked at the results across different subgroups within the participants. For example, ginkgo appeared to reduce the risk of developing Alzheimer's disease in men and in alcohol consumers by more than half when these groups were considered separately. And when only people who used ginkgo or placebo for four years or more were considered, ginkgo appeared to have a protective effect.
The study authors note that, "Conclusions from this trial were restricted by the lower than expected incidence of Alzheimer's disease. Further studies about long-term exposure to standardised ginkgo biloba (sic) extract might be warranted."
Putting it in perspective
It is hard to pool data from multiple trials and reach a sound conclusion, and since other research has shown protective effects against Alzheimer's Disease before, this new study, with its primary finding, is hard to place within the body of evidence.The research on ginkgo is in agreement about its safety: for most people, taking ginkgo poses no risks. Here are some other safe measures to take to prevent memory loss and dementia:
(Lancet Neurology 2012; http://dx.doi.org/10.1016/S1474-4422(12)70206-5)
Maureen Williams, ND, completed her doctorate in naturopathic medicine at Bastyr University in Seattle and has been in private practice since 1995. With an abiding commitment to access to care, she has worked in free clinics in the US and Canada, and in rural clinics in Guatemala and Honduras where she has studied traditional herbal medicine. She currently lives and practices in Victoria, BC, and lectures and writes extensively for both professional and community audiences on topics including family nutrition, menopause, anxiety and depression, heart disease, cancer, and easing stress. Dr. Williams is a regular contributor to Healthnotes Newswire.