Ask the doctor: Can supplements prevent dementia?
Q. Is there any medication or over-the-counter supplement or vitamin I can take to prevent dementia?
A. Unfortunately, no drug, supplement, or vitamin can prevent you from getting dementia. The 2010 Consensus and State-of-the Science Statement on Preventing Alzheimer's Disease and Cognitive Decline from the National Institutes of Health reviewed all the available scientific evidence on the topic. The authors concluded, "Evidence is insufficient to support the use of pharmaceutical agents or dietary supplements to prevent cognitive decline or Alzheimer's disease." So there are currently no good scientific data to show that taking anything—whether it's ginkgo biloba, vitamin E, or donepezil (Aricept)—will protect you from losing mental function.