Effect on age-related cognitive decline
Multiple investigations have looked at the effects of Gingko Biloba on brain aging. In particular, looking at the effect Ginkgo supplementation can have on memory, attention, executive processing, and other cognitive domains. The evidence is conflicting. However, large-scale studies point to Gingko Biloba having no measurable improvement in cognition in aging adults.
In one study, administration of a Gingko Biloba extract (Tanakan) for three months, significantly improved measures of reaction time and cognitive efficiency.1. In a 1998 study, improvements in short-term memory were observed with Gingko supplementation but were nominal compared to placebo.
However, many criticisms have been leveled at these and other studies, about the methodologies used and the analyses conducted. In one 2009 meta-analysis of published literature on Gingko Biloba, the authors concluded that many of the previous studies of Gingko were small, had unreliable methodologies, and were potentially subject to positive publication bias. In 2002 and 2009 studies published in JAMA, short-term, and long-term Gingko Biloba use, respectively, were investigated. In the 2002 study, published in the Journal of the American Medical Association (JAMA), the effect of 6 weeks of gingko administration on neurophysiological tests of learning, memory, attention, and concentration were assessed in 219 adults over 60 years old. No improvement over placebo was observed for any domain of cognition. In the 2009 study, also published in JAMA, comprehensive neurophysiological testing was done to investigate the effect of 120 mg of gingko, taken twice daily, in 3069 adults aged 72-96 years old. This longitudinal study asked whether Ginkgo taken for multiple years could prevent age-related cognitive decline. Gingko administration did not improve any cognitive domains, compared to placebo.