FORGET ABOUT GINKGO
A thorough study published in the Journal of American Medical Association concludes that there appears to be no benefit in taking ginkgo supplements to prevent dementia. A group of patients who took 120mg of ginkgo extract twice daily did no better than patients who took a placebo. Sadly, no benefits were identified.
Exercise, socializing, reading and general keeping mentally and physically active have been shown to help delay or prevent several types of age related mental decline.
Spend your ginkgo money on a good book or a pair of walking shoes.