Ginkgo biloba has long been touted as an herbal remedy for better memory, improved cognition and even as a treatment for Alzheimer's disease. But a new study published this morning at the website for the journal The Lancet Neurology says that people who take ginkgo while hoping to slow or stop the progression of Alzheimer's are, essentially, wasting their money.
The study, which looked at a specific brand of standardized ginkgo extract, followed more than 2800 elderly French patients for 5 years. Of the patients, 1406 of them took the ginkgo extract while 1414 of them were given a placebo product. All of the patients had sought treatment for memory problems at some point and by the end of the study 61 of the ginkgo takers had been formally diagnosed with Alzheimer's disease. That compares to 73 of the placebo users.
About the only good news to come out of this study--at least if you're a believer in ginkgo--is that the extract did seem to be safe. A similar number of patients in both groups died over the course of the study and only a few more of the ginkgo patients had a stroke during that time.
Herbalists believe that ginkgo works, in part, by increasing blood flow to the brain. Unfortunately, recent studies on both elderly and younger patients have not found the increased blood flow to be beneficial. A 2005 study, for example, found that college kids who took the remedy got a short-term boost in memory but after a few weeks the ginkgo stopped working. The students, the researchers speculated, eventually developed a resistance to the herb.
And while some studies on Ginkgo biloba have produced promising results large double-blind studies have generally not.