Taking the herbal supplement ginkgo biloba may delay the onset of cognitive impairment in elderly adults. However, the study also showed a higher incidence of strokes and “mini-strokes” in ginkgo users.
During the course of the study, 14 of those who took the placebo developed memory problems, but only 7 of those who took the ginkgo extract did. When the researchers took into account whether people followed directions in taking the study pills, they found that people who reliably took ginkgo had a 68 percent lower risk of developing memory problems.
Seven people taking ginkgo had strokes, while none of those taking placebo did.