Study: Ginkgo doesn't cut dementia risk

The popular herb ginkgo biloba does not reduce the risk of dementia or Alzheimer's disease, according to a study of more than 1,500 elderly patients who took the supplement. Often touted as a way to preserve aging memories, no large-scale, randomized clinical trial -- until now -- has thoroughly evaluated the safety and effectiveness of ginkgo biloba extract as a way to prevent dementia.