GINKGO bilobais the oldest and longest-living species of tree in the world. It has a lifespan of up to 1,000 years and is a medicinal fountainhead.Record of ginkgo providing health benefits dates back thousands of years. In Germany, a world leader in herbal research, it’s the most commonly prescribed herbal medicine.Ginkgo, or maidenhair, as it is often called, is native to the Far East, and was near extinction before cultivation for medicinal purposes assured its survival. The name biloba describes the tree’s two-lobed leaf, which, philosophically, is considered to represent unity within duality.Ginkgo is arguably the most widely used and studied of all herbs.Ginkgo’s main effect is on our vascular or circulatory system. It improves blood flow and oxygen and nutrient delivery throughout the body via deep-seated medium and small arteries. Increasing blood flow to the brain can help with memory loss, difficulty concentrating and dizziness caused by deficient blood flow.In healthy young and middle-aged people, ginkgo has been shown to help with memory and speed of mental processing.Ginkgo is a therapy to consider especially for elderly people with mild to moderate dementias, such as Alzheimer’s, caused by cerebral vascular insufficiency or reduction of blood supply to the brain.THE herb also aids in improving circulation in the arms and legs, and should be considered for conditions of vascular insufficiency, such as intermittent claudication, characterized by leg pain while walking, and Raynaud’s disease, characterized by periodic chilling, pain, skin discoloration and numbness of extremities. Both are ailments caused by decreased blood flow.Other conditions involving circulation, such as macular degeneration, glaucoma and diabetic retinopathy, may be improved with ginkgo. The herb may also be considered to reduce and prevent varicose veins. Other therapeutic uses include treating physiologic sexual dysfunction in men, angina and premenstrual symptoms such as breast tenderness and mental or emotional jags.Different plants have different points of impact on the circulatory system. Crataegus or hawthorn-tree herbal preparations act mainly on the coronary vessels; horse chestnut on the venous system; and ginkgo on the cerebral vessels and peripheral vessels of the body.Most of the research on ginkgo has been done with standardized leaf extracts from young trees containing 24% flavone glycosides and 6% terpene lactones.When shopping for ginkgo, these percentages are what to look for on the label to assure a reputable product.While the roasted seeds of ginkgo are a delicacy in China and Japan, I’d suggest consuming only properly labeled and bottled leaf-extract products, as consumption of other parts of the tree, including the seeds, can prove deadly.AS is often the case with herbal medicine, studies indicate it is the synergistic effect of all the constituents in the leaf, rather then one particular chemical compound, that creates ginkgo’s therapeutic value. Complementing the circulatory benefits of ginkgo are a host of powerful antioxidants that reduce inflammation in the body and protect the integrity of our DNA, improve cellular energy production, enhance nerve transmissions in the brain and reduce the risk for blood clots. Biologist, geneticist and author Paris Kidd suggests that the antioxidant properties ofginkgo specifically protect and thereby reduce the degradation of cerebral nerve fibers seen with dementias such as Alzheimer’s disease.Standardized ginkgo leaf extracts at doses ranging from 40-80 milligrams three times a day are considered safe. Avoid crude ginkgo plant preparations because of the potentially deadly toxic compounds contained in the fruit pulp and seeds. If pregnant or taking any prescription medications, consult a physician before taking ginkgo. Discontinue ginkgo use two weeks before undergoing any surgery.Side effects are uncommon; however, headaches may occur if a person takes too much too soon, so start with about 50 milligrams daily and work your way up after a week or two if you’re not getting the results you expect. Reports of gastrointestinal upset, dizziness, palpitations, constipation and allergic skin reactions do exist, although I have never seen anyone experience these side effects.Jon Dunn is a naturopathic physician living in Nosara, on the northern Pacific coast. E-mail questions or comments to firstname.lastname@example.org, or visit www.drjondunn.com.