Ginkgo biloba, hereafter referred to as ginkgo, has a variety of medicinal uses. Ginkgo extract has been used for thousands of years in Chinese medicine to improve a variety of conditions, including memory and heart health. In fact, the ginkgo tree originates in China.
In Germany, the Commission E is similar to the Food and Drug Administration in the United States except that the Commission E carefully studies the research on traditional, folk, and herbal medicine. This prestigious group of experts has approved the standardized extract of ginkgo as a pharmaceutical medicine in Germany because both scientific and clinical studies found ginkgo extract to be effective. The conclusion was based on a 210-page detailed written study (monograph) on ginkgo research of which no effects were observed from dried ginkgo leaf. The Commission E has also concluded that ginkgo leaf (as opposed to the extract) is an unapproved drug due to lack of evidence of its usefulness.
So read the label of your product. Is the word ‘extract’ written next to ginkgo on the ingredients list? If not, it means that they have ground up ginkgo leaves in it and not extract. It also means that you might be wasting your money. Perhaps that’s one of the reasons why some people received no benefit while other people do.
An important thing to note about ginkgo is the possibility of allergic reactions. People with a history of severe allergic reactions to poison ivy, mangoes, and cashews are more likely to experience allergic reaction when consuming non-standardized ginkgo supplants. This is because non-standardized ginkgo supplements might contain more than 5 ppm of the allergenic substance while the level of these allergens in standardized pharmaceutical preparations of ginkgo was restricted to 5 ppm or less by the Commission E.
In 1997, a placebo controlled study was done on more than 300 Alzheimer’s patients. Forty milligrams of ginkgo extract was taken three times a day for a six month to one year period. The result was improved cognitive performance and social functioning in a large number of Alzheimer’s patients compared to the placebo group. The study was then published in the Journal of the American Medical Association.
Studies have found that ginkgo extract increases blood circulation and nutrient delivery to brain cells.  Increasing the flow of blood in people with poor circulation may have a wide variety of benefits:
- Increased blood flow to the genitals may benefit one’s sex life.
- Improved blood flow to the extremities may benefit those with cold hands and feet, including conditions such as Raynaud’s.
- Improved blood flow to the optic nerve may benefit certain eye conditions caused by poor blood flow. 
A study was done on 52 people with acquired sensorineural hearing loss (SNHL). Some of the patients were treated with conventional drugs, and the rest were treated with ginkgo extract. The conventional group demonstrated a drug efficacy of 30% while in the ginkgo group it was up to 60%.
The improvement in tinnitus was 52% in those treated with the ginkgo extract compared to 50% for those treated with the conventional drugs (Neurobion, Arlidine & Vit -A).
Ginkgo is contraindicated for those on blood thinning drugs because the herb has blood thinning properties and the result of mixing ginkgo and blood thinners may lead to internal or excessive bleeding. This also goes for aspirin and ibuprofen as they also have blood thinning properties. Taking higher doses of gingko extract than recommended may also cause excessive bleeding.
As a child, I learned that ginkgo is the oldest surviving species of tree on the earth. There was a ginkgo tree on the front lawn of my childhood home and I started making my own ginkgo tinctures in the 1990s. I have been using ginkgo leaf extract on and off for more than 20 years.
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