Ginkgo and memory loss
A new study suggests ginkgo supplementation is useful in preventing memory loss in old people, but there may be associated increased risk of stroke:
"Among 118 people 85 or older, those who took the supplement reliably had a 70% lower risk of developing mild memory problems than those who took a placebo, Hiroko Dodge, Ph.D., of Oregon State University here, and colleagues reported online in Neurology.
However there were six strokes and one TIA among those taking ginko and none in the placebo group."
More on the report here.