Sandra Justice, P.D., FACA
Ginkgo biloba is one of the oldest living tree species, existing even before the Ice Age. Although Chinese herbal medicine has used both the ginkgo leaf and seed for centuries, modern research has focused on the standardized Ginkgo biloba extract (GBE), which is produced from the leaves. This extract is highly concentrated and much more effective than any other use of the leaves. Ginkgo has powerful therapeutic properties for a number of serious medical conditions, including Alzheimer’s disease, asthma, impotence, tinnitus and hearing loss, headaches, circulatory disorders and hemorrhoids.
GBE is of the greatest interest to modern-day chemists and herbalists. The average drug/extract ratio is 50:1. The extract is characterized by 22-27 % flavonone glycosides and 5-7% terpene lactones, which should appear on the supplement label. GBE is marketed in both solid and liquid forms with each dose usually containing 40mg of the standardized extract. This mixture of biologically- active natural products gives the whole extract its complex range of activity.
Applications in Alzheimer’s Disease
Numerous studies have shown the efficacy of using GBE to improve the mental acuity of geriatric patients. The extract strengthens tissue by stabilizing cell membranes, acting as an antioxidant, and inhibiting free radical damage. It also aids cell use of oxygen and glucose. These properties are particularly important for brain cell tissue, which is most vulnerable to free radical damage and oxygen deprivation. Brain cells are also protected by GBE’s ability to improve blood circulation to the brain. GBE has also been shown to increase the rate of transmission of information to the nerve cell level, enhancing memory ability. These combined effects allow GBE to reverse mental deterioration caused by vascular insufficiency. The mental deterioration caused by Alzheimer’s seems to be significantly delayed by GBE’s ability to enhance brain function, particularly during the early stages of the disease.
Peripheral arterial insufficiency is caused by arterial narrowing or obstruction and its most common symptom is intermittent claudication, particularly in the calves. GBE has been shown to improve blood flow in the limbs and increase walking tolerance. Other peripheral vascular disorders that respond to GBE include diabetic peripheral vascular disease, Raynaud’s phenomenon, acrocyanosis, and postphlebitis syndrome.
The terpone lactones in GBE (ginkgolides and bilobalide) also protect nerve cells from damage during periods of ischemia or hypoxia. This hypoxic tolerance is seen particularly in cerebral tissue, making GBE an effective treatment for people who have suffered strokes or transient ischemic attacks.
Modern Chinese pharmacy references still list fruit and leaf extracts of ginkgo biloba as being beneficial in treating chronic bronchitis and asthma. Constriction of the bronchial tubes has been inhibited in the presence of PAF-antagonistic ginkgolides in these extracts.
Since ginkgo biloba extract has been used successfully to treat blood pressure regulation and various vascular diseases, it should come as no surprise that ginkgo has a beneficial application in dealing with impotence. The extract has the ability to increase blood flow without changing systemic blood pressure. GBE may be an effective alternative to other vasodilators that may be contraindicated in men with angina, glaucoma, heart disease, myocardial infarction, or a recent stroke.
Ginkgo biloba extract serves as an antioxidant and a free-radical scavenger and as such may be a possible deterrent to macular degeneration. Studies suggest that ginkgo extract might also be useful in deterring free-radical damage to the retina of the eye, as well as diabetic retinopathy.
Daily doses of ginkgo biloba extract for dementia syndromes range from 120-240mg taken in 2 to 3 divided doses with meals.
Daily doses for tinnitus, vertigo, impotence, eye disorders, and asthma range from 120-160mg in 2 to 3 divided doses with meals.
Results often take four to six weeks, but should continue to accumulate. Some dramatic changes may not appear for six months. Consult a healthcare professional involved in nutritional programming to find the most effective product for you. Ginkgo should not be considered a replacement for your prescribed medications. It may serve as a preventative tool or be useful as an addition to your drug therapy. As always, it is wise to consult your physician or pharmacist before adding a nutrient to your present drug therapy.
Side Effects/ Contraindications
Consumption at the doses listed above rarely poses health risks. Side effects may include gastrointestinal disturbances, headache, and allergic skin reactions. Since ginkgo biloba inhibits platelet-activating factor it may increase bleeding tendencies in combination with other drugs that inhibit blood platelet aggregation. There are no restrictions known for use in pregnancy and lactation.
The 200 million-year-old healer
Few herbal remedies have been as extensively researched as has ginkgo biloba extract, and the supplement seems to be one of our most useful therapies for many complaints. Ginkgo biloba is an exceptional therapeutic agent for the treatment of some patients with Alzheimer’s disease, asthma, impotence, tinnitus, and various other circulatory disorders. Its efficacy has been well documented throughout time.