How Ginkgo Biloba Affects Memory and Stroke Risk

Ginkgo biloba capsules
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Ginkgo biloba is one of the most popular supplements used around the world. Also known as the maidenhair tree, it is widely popular for improving memory and preventing cognitive problems such as dementia. However, researchers are finding out ginkgo biloba may not be as effective as once thought. What's more, it may increase the risk of a dangerous, yet common medical condition.

The Research

Researchers enrolled 118 people over age 85 with no memory or other cognitive problems in a study, published in 2008 in the journal Neurology, to find out the impact of ginkgo biloba on memory and dementia. Half of the people took a ginkgo biloba supplement three times a day, and the other half took a placebo. Researchers followed up with them for three years. Over the course of the study, 21 people developed mild memory problems; 14 of those people were taking the placebo, and seven were taking to ginkgo extract. But it's not all good news for ginkgo. The difference between the ginkgo and placebo groups was not statistically significant. In other words, the fact that the placebo group had more cases of memory problems could have been just random change.

The Reality

During the aforementioned study participants were found to not having taken the proper dosage of the supplements. When the people who were not taking their ginkgo biloba three times daily were removed from the analysis, the remaining ginkgo biloba takers had 68% less risk of developing mild memory problems over three years. This would seem like a significant lowering of risk, however, the studies findings also revealed an uptick in risk.

Stroke Risk

The group taking the ginkgo biloba extract properly had more strokes and mini-strokes than the placebo group. Researchers concluded that more research needs to be done to better understand the benefits and risks of ginkgo biloba and brain health. In a recent review of studies related to Ginkgo biloba supplementation, Ginkgo biloba was found to show improvement of cognitive function, activities of daily living, and global clinical assessment in patients with mild cognitive impairment or Alzheimer's disease. However, because many studies are limited in sample size, some findings were inconsistent and the methodological quality of included trials was shoddy, more research is warranted to confirm the effectiveness and safety of ginkgo biloba in treating mild cognitive impairment and Alzheimer's disease.

Bottom Line

Right now, it doesn’t seem like a good idea. There could be something to the claims that ginkgo biloba can improve memory (or at least slow memory decline), but the evidence isn’t strong enough, and the possible increase in stroke risk is just too high. There are also multiple forms of ginkgo biloba in the marketplace. Until researchers figure out which forms are harmful and in what dosage, it seems best to stay away. Instead of looking for a pill, consider these mental fitness techniques to keep your brain sharp.

View Article Sources
  • Guoyan Yang, Yuyi Wang, Jin Sun, Kang Zhang and Jianping Liu. Ginkgo Biloba for Mild Cognitive Impairment and Alzheimer’s Disease: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Current Topics in Medicinal Chemistry. 2016; Vol. 16 Issue 5 pp. 520-8.
  • H. H. Dodge PhD*, T. Zitzelberger MPH, B. S. Oken MD, D. Howieson PhD, ABPP, and J. Kaye MD. A randomized placebo-controlled trial of ginkgo biloba for the prevention of cognitive decline. Neurology, online February 27, 2008.