For thousands of years, leaves from the Ginkgo biloba tree have been a common treatment in Chinese medicine. In the U.S., many take ginkgo supplements in the belief that they will improve memory and sharpen thinking.
Why do people take ginkgo?
Ginkgo improves blood flow to the brain and acts as an antioxidant. These effects may translate into some benefits for certain medical problems, but the results have been mixed.
Some studies have found that in healthy people, ginkgo might modestly boost memory and cognitive speed. Other studies have not found a benefit.
Several ginkgo studies have shown that it can help with memory problems caused by dementia or Alzheimer’s disease. It seems to help prevent the progression of dementia symptoms, especially if the dementia is thought to be the result of atherosclerotic vascular disease. It does not seem to prevent dementia or Alzheimer’s, however.
There's good evidence that ginkgo might ease leg pain caused by clogged arteries. It might also help with some other circulation problems. In addition, ginkgo may relieve PMS symptoms, like breast tenderness and mood changes.
Researchers have studied ginkgo for many other conditions, including ADHD, depression and other psychological conditions, multiple sclerosis, and tinnitus from a vascular origin. Some people are also using ginkgo to prevent high altitude sickness, though studies have not yet established that it’s effective for that. Many uses of ginkgo show promise, but more research needs to be done.
How much ginkgo should you take?
There is no standard dose of ginkgo biloba supplements. However, in medical studies, almost all clinical trials have used a standardized extract of ginkgo, standardized to 24% flavone glycosides and 6% terpene lactones. A common dose in people with dementia is 40 milligrams of that extract three times daily. For improving cognitive function in healthy people, studies have used between 120 milligrams to 600 milligrams of the extract daily.
No matter why you're using ginkgo, experts suggest starting at a low dose (120 miligrams daily) and increasing gradually. Get advice from your doctor.