Ginkgo Biloba Extract: A Review

Extracts of the leaves of the Ginkgo biloba tree (ginkgo) have been used in China for medicinal purposes for hundreds of years. Research performed during the past fifteen years suggests that ginkgo may be of value in the treatment of age-related physical and mental deterioration, dementia, peripheral vascular disease, and organic impotence. Ginkgo may also reduce the severity of depression in individuals with cerebral dysfunction. Preliminary or uncontrolled studies suggest that ginkgo may benefit some patients suffering from tinnitus, vertigo, acute cochlear deafness, macular degeneration, cyclic edema, and asthma. (Alt Med Rev 1996;1(4):236-242) The Ginkgo biloba tree (ginkgo) is the oldest tree on earth: more than 200 million years old.1 Individual ginkgo trees sometimes live more than 1,000 years. For those of you who believe that nature is a metaphor, it should not be surprising that extracts of the leaves of the oldest tree on earth have been shown to exhibit what might be described as “anti-aging” effects. Even if you do not wish to grant Mother Nature that poetic license, there is a considerable amount of scientific research supporting the use of ginkgo as a treatment for age-related problems, as well as for other disorders. Medicinal use of ginkgo leaves was mentioned as early as 1505 in a Chinese herbal text. In modern Chinese medicine, ginkgo is recommended to improve brain function and to relieve asthma. During the past fifteen years, ginkgo has been studied extensively by European scientists and has been found to be useful against a wide range of disorders, particularly conditions that are associated with aging. Annual sales in Europe, where ginkgo is approved as a prescription drug, amount to about $500 million. Standardized extracts of ginkgo were introduced into the United States in the mid 1980’s; they are currently available without a prescription. Ginkgo is said to be effective for a wide range of clinical conditions, many of which are seemingly unrelated in their etiology and pathogenesis. However, the broad therapeutic spectrum of ginkgo may be explainable in part by the fact that it influences two fundamental aspects of human physiology: 1) it improves blood flow to the brain and other tissues and 2) it enhances cellular metabolism. Because these functions are essential for good health, it is not unreasonable to consider the possibility that ginkgo might have a broad spectrum of clinical applications. Most of the illnesses relieved by ginkgo are associated with old age, a time of life when both blood flow and cellular metabolism deteriorate. Other disorders that may respond to ginkgo, including asthma, tinnitus, vertigo, and impotence, can also occur earlier in life.