Gingko (Ginkgo biloba, Madenhair tree)

The Ginkgo tree grows most prominently in the southern and eastern US, southern France, China, and Korea. The leaves of the tree are used medicinally for treating various conditions,  including asthma, allergies and coughs. Ginkgo stimulates circulation in the brain, ears, and other parts of the body; it is also an antioxidant. Plant scientists believe that the most active constituents of ginkgo are the flavonoid compounds flavoglycosides and ginkgoheterosides.

ROLE FOR ANTI-AGING:

Bioflavonoids are primarily responsible for Gingko’s antioxidant activity and these may inhibit platelet aggregation. These actions may help Gingko protect against cardiovascular diseases such as atherosclerosis and support the brain and central nervous system. Unique terpene lactone components found in Gingko leaves, called ginkgolides and bilobalide, are associated with increased circulation to the brain and other parts of the body, they also help to protect nerve cells from oxidative damage. Recent animal studies indicate that bilobalide protects neurons from apoptosis (programmed cell death) and excitotoxic damage. In a recent study of patients with Alzheimer’s type senile dementia, those who took ginkgo extract  three times per day experienced significant improvements in memory and attention. The changes were evident after one month and continued to accumulate over the three month period of the study.

The most popular ginkgo products are encapsulated extracts standardized to 24% of chemicals called flavoglycosides; you can also find liquid herbal concentrates and the powdered whole herb. An average dose of the standardized extract is 40 to 60mg. IMPORTANT: Ginkgo leaves contain a group of potentially toxic chemicals known as alkylphenols. The German  health commission, Commission E states that ginkgo supplements must not contain more than 5 parts per million of these toxic compounds. The ginkgo extracts EGb 761 and LI 1370 both conform to these strict safety limits.

Ginkgo has been associated with no longterm toxicity and few side effects. However, newcomers to the herb who take single doses in excess of 300mg or so may experience headaches or dizziness. Some ginkgo users may also experience a mild upset stomach. Until recently, gingko was not contraindicated for pregnant and lactating women, however in August 2001 researchers at a Detroit university found that women taking one type of the supplement had high levels of the toxin colchicine, which can cause birth defects. For this reason alone,  pregnant women, breastfeeding women, and women planning to conceive should not take gingko supplements.