Ginkgo has been extensively researched for its possible benefits to the elderly. Studies indicate ginkgo has the ability to increase circulation which can lead to enhanced memory. (
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2) This effect can in turn delay the onset of Alzheimers and reduce the effects of senile dementia, tinnitus, and vertigo.(
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6) Studies indicate that ginkgo's support of healthy brain function is related to its ability to increase blood flow to the brain, thus improving delivery of nutrients and disposal of waste products.(
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The effectiveness of ginkgo in treating dementia is debated. Numerous studies have been completed evaluating numerous patients with various types of demetia, including Alzheimer's disease. These studies have had very differing results. In a study involving over 200 patients, a standardized ginkgo preparation (40mg three times a day) was compared to placebo. The ginkgo was reported safe and capable of stabilizing and improving mental and social functioning for up to a year.(8) Another trial involving over 200 patients, compared the same ginkgo preparation with placebo and reported no advantage with the gingko when used for 24 weeks.(9) A third trial compared 115 people over 60 years old using ginkgo to 115 people over 60 years old using placebo. The study evaluated these participants using 15 different tests for memory and learning. The results of this study showed no improvement in the tests for both the ginkgo and the placebo group.(10)
Four commonly used medications for dementia (tacrine, donepezil, rivastigmine, and metrifonate) were compared to a standardized ginkgo extract and a placebo for their use in Alzheimer's disease. The authors concluded that second-generation cholinesterase inhibitors (donepezil, rivastigmine, and metrifonate) and the standardized ginkgo extract should be considered equally effective in the treatment of mild to moderate Alzheimer's disease.(11)
Because of its effects on the circulatory system, ginkgo may also ease the leg pain that arises from intermittent claudication and similar disorders.(12),(13) One study even found that ginkgo performed as well as a leading prescription medication for treating intermittent claudication.
Ginkgo's ability to support healthy circulation and brain function has applications in younger populations as well. Disorders it may improve include diabetes and various circulatory conditions including cyanosis and Raynaud's Syndrome.(14)
Ginkgo has also been used to treat impotence, especially when associated with antidepressant therapy.(15),(16) Ginkgo may also be involved in a chemical process that reduces the potential for clot formation in the blood by inhibiting platelet activating factor (PAF).(17) Scientists think this function, along with a potential ability to dilate blood vessels, accounts for its record of use in treating asthma in China for thousands of years.
Finally, ginkgo is an antioxidant, giving it the ability to help rid the body of free radicals and thus lessen the risk of chronic degenerative diseases.(18) Also due to the antioxidant activity of ginkgo, it may help treat macular degeneration(19) and decrease the damaging effects of radiation, chemotherapy,(20) and certain medications.(21)