Monograph

As a powerful antioxidant, Ginkgo Biloba contains unique free radical fighting properties, flavone glycosides and terpene lactones, which may improve circulation, sustain mental clarity, and maintain the tone and elasticity of arteries and capillaries. If you are on blood-thinning medications (coumadin, aspirin, heparin, or plavix), please talk to your doctor prior to taking any product containing Ginkgo Biloba
 

Description

NUTRAscriptivesâ Ginkgo Biloba is sourced from a European extractor that complies with high-quality standards to produce a balanced, concentrated formula of ginkgo biloba extract (24% ginkgo flavone glycosides, 6% terpene lactones). One of the oldest living trees, ginkgo biloba can survive over 1,000 years and grow 120 feet. The leaves contain two types of flavonoids and terpenoids that have antioxidant properties.

Research

Cardiovascular Function

The excessive development of free radicals in the heart can lead to various cardiovascular conditions. Ginkgo has shown promising results in reducing oxidative stress in several heart studies. A meta-analysis of ginkgo's effects indicated an improvement in circulation among patients with blocked arteries.[1] Another study found ginkgo extract deterred the formation of lipid oxidation during common injuries that forms after restoring oxygen and blood flow to blocked arteries.[2]

Stress-Reducer

Stress can affect learning and memory function, as excessive amounts of glucocorticoid hormones released after a distressing event can affect cognitive function. Individuals with moderate memory impairment received 120 mg per day of ginkgo for three to six months. Results indicated that subjects had greater cognitive function and improvement in coping with daily activities,[3] especially when taken for six months. A recent study observed that ginkgo prevented chronic stress in rats improving spatial memory function in the rats that received ginkgo.[4] Another behavioral study in rats found ginkgo reduced corticosteroid levels that are stimulated from stress by 50%.[5]

Individuals with limited cognitive function can also experience a depressed mood. An eight-week study recruited 40 patients with poor dispositions to observe the effects of ginkgo on enhancing their mood. Results indicated a significant improvement in mood among patients that received ginkgo when compared to the placebo group.[6]

Improve Circulation

Ginkgo is often used to treat circulatory problems. It increases blood flow to the brain, improves memory, and dilates blood vessels reducing the clumping of blood platelets. One study found ginkgo improved blood flow to the brain and alleviated age-related increases in blood pressure in rats after three-weeks of treatment.[7]

Reduced oxygen and blood flow to arteries in the legs can cause leg cramps and walking problems. A meta-analysis reviewed six to twelve month ginkgo treatment studies in relation to leg circulation finding a general improvement in walking performance.[8]

Ginkgo can decrease pressure on artery walls and improve circulation in vital organs. An animal study found administering ginkgo to rats relieved pressure in the veins and improved circulation in the liver.[9] Another study with rats found ginkgo protected the brain from circulation deficiencies that form oxidative stress.

Supplementing with ginkgo has shown promise in improving lung function by dilating bronchial tubes and decreasing inflammatory cells. Ginkgo was given to 75 subjects with constricted breathing problems for two or four weeks. The expansion in breathing activity suggested ginkgo could complement traditional therapies used for constricted breathing.[10]

Impotence

One possible cause of impotence is found in circulatory problems. Ginkgo improves microcirculation and relaxes vascular walls; thus, it has profound effects on ailments related to aging.[11] Ginkgo has been seen as a treatment for improving impaired blood flow. A study that included 60 patients with impotence found six to eight weeks of ginkgo supplementation improved blood flow in 50% of the patients.[12]

Ginkgo improves blood flow throughout the body by restoring the nitric oxide balance.[13] The herb was given to 80 patients with cardiovascular ailments, as coronary blood flow is commonly impaired in these individuals. Results indicated that ginkgo increased nitric oxide function improving blood flow throughout the arteries.19

As individuals age, endothelial function decreases altering coronary blood flow. One study recruited 60 healthy elderly adults to take ginkgo or a placebo. Results indicated ginkgo increased coronary blood flow and improved endothelial function by increasing dilation of the arteries.[14]

Cognitive Function

An insufficient amount of oxygen in the brain can lead to greater levels of oxidative stress and negative cognitive conditions. Ginkgo promotes circulation in the brain to improve memory function, alertness, and overall cognitive health. One study compared multiple doses of ginkgo with a single daily dose to see if there were any differences in the effects on short-term memory among healthy middle-aged subjects. The results indicated a single, daily dose of 120 mg of ginkgo was most effective in improving short-term memory.[15]

A six-week clinical trial of 262 healthy individuals, from 60 years of age and older, found that 180 mg per day of ginkgo improved memory scores and self-perception of memory, when compared to the placebo group.[16] A similar study of 62 healthy subjects found ginkgo improved mental function in only four weeks.[17]

A critical review of 40 clinical trials, where ginkgo was given in a daily dose of 120 mg to 160 mg for four to six weeks, indicated ginkgo improved memory function. Furthermore, the review found ginkgo is a safe-treatment for improving overall cognitive function associated with decreased circulation in the brain.[18] Among 202 individuals with cognitive insufficiencies, ginkgo significantly improved cognitive and social functioning, when taken for six months to one year.[19]

A recent pilot-study investigated the effects of ginkgo on children (5-16 years old) with reading difficulties. Results indicated 80 mg per day of ginkgo was tolerable and may be a beneficial treatment for reducing learning impairments. More studies need to be conducted to observe the possibilities.[20]

Additional Information – Dosage & Interactions

Suggested Use

As a dietary supplement, take one capsule, or as directed by a physician.

Dosage

120 mg to 160 mg per day to aid circulation; 240 mg per day to improve cognitive abilities and balance mood

Precautions

The maximum safe dosage of this supplement has not been determined for children, pregnant or nursing women, or those with severe liver or kidney disease. As with all supplement regimens, please consult your physician prior to use.

Occasional gastrointestinal upset, allergic skin reaction and headache. Due to its blood thinning properties, care should be used by individuals with blood clotting problems or those taking anticoagulant medications.

Drug Interactions

Consult your physician before supplementing with Ginkgo Biloba if you are taking the following medications.

Blood thinning medicine (Coumadin, Plavix, etc.); Pain Relievers (Advil, Motrin, etc.), Naproxen (Aleve, etc.); Anti-Depressants (Zoloft, Paxil, etc.); High blood pressure medicine (Cardizem, Cardene, etc.); Anti-convulsants (Dilantin, Tegretol, etc.); and/or Insulin.

*Statements made herein have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.

References

[1] Horsch S, Walther C. Ginkgo biloba special extract EGb 761 in the treatment of peripheral arterial occlusive disease (PAOD)--a review based on randomized, controlled studies. Int J Clin Pharmacol Ther. 2004 Feb; 42(2):63-72.

[2] Haramaki N, Aggarwal S, et al. Effects of natural antioxidant ginkgo biloba extract (EGB 761) on myocardial ischemia-reperfusion injury. Free Radic Biol Med 1994; Jun; 16(6):789-794.

[3] Rai GS, Shovlin C. and Wesnes KA. A double-blind, placebo-controlled study of ginkgo biloba extract in elderly out-patients with mild to moderate memory impairment. Current Medical Research and Opinion. 1991; 12:350-355.

[4] Walesink A, Braszko JJ. Preventive action of Ginkgo biloba in stress- and corticosterone-induced impairment of spatial memory in rats. Phytomedicine. 2007 May 3.

[5] Amri H, Drieu K, Papadopoulos V. Ex vivo regulation of adrenal cortical cell steroid and protein synthesis, in response to adrenocorticotropic hormone stimulation, by the ginkgo biloba extract EGb 761 and isolated ginkgolide B. Endocrinology 1997; 138(12):5415-5426.

[6] Rigney U, Kimber S, Hindmarch I. The effects of acute doses of standardized ginkgo biloba extract on memory and psychomotor performance in volunteers. Phytother Res. 1999; 13(5): 408-415.

[7] Sasaki Y, Noguchi T, Yamamoto E, et al. Effects of Ginkgo biloba extract (EGb 761) on cerebral thrombosis and blood pressure in stroke-prone spontaneously hypertensive rats. Clin Exp Pharmacol Physiol. 2002 Nov; 29(11):963-967.

[8] Schneider B. Ginkgo biloba extract in peripheral arterial diseases. Meta-analysis of controlled clinical studies. Arzneimittelforschung 1992; Apr; 42(4):428-436.

[9] Zhang CQ, Zhu YH, et al. The effect of Ginkgo biloba extract on portal hypertension and hepatic microcirculation in rats. Zhonghua Gan Zang Bing Za Zhi. 2007 Apr; 15(4):245-248.

[10] Tang Y, Xu Y, et al. The effect of Ginkgo Biloba extract on the expression of PKCalpha in the inflammatory cells and the level of IL-5 in induced sputum of asthmatic patients. J Huazhong Univ Scit Technolog Med Sci. 2007 Aug; 27(4):375-380.

[11] Yoshikawa T, Naito Y, Kondo M. Ginkgo biloba leaf extract: review of biological actions and clinical applications. Antiox & Redox Signaling. 1999; 1(4):469-480.

[12] Sikora R, et al. Ginkgo biloba extract in the therapy of erectile dysfunction. J Urol. 1989; 141:188A.

[13] Wu YZ, Li SQ, Zu XG, Du J, Wang FF. Ginkgo biloba extract improves coronary artery circulation in patients with coronary artery disease: contribution of plasma nitric oxide and endothelin-1. Phytother Res. 2008; 22(6):734-739.

[14] Wu YZ, Li SQ, Zu XG, Du J, Wang FF. Ginkgo biloba extract improves coronary blood flow in healthy elderly adults: role of endothelium-dependent vasodilation. Phytomedicine. 2008; 15(3):164-169.

[15] Rigney U, Kimber S, Hindmarch I. The effects of acute doses of standardized ginkgo biloba extract on memory and psychomotor performance in volunteers. Phytother Res. 1999 Aug; 13(5):408-415.

[16] Mix JA, Crew WD. A double-blind, placebo controlled randomized trial of Ginkgo Biloba extract EGb761 in a sample of cognitively intact older adults: neuropsycological findings. Human Psychopharmacology Clin Exp. 2002; 17:267-277.

[17] Cieza A, Maier P, Poppel E. Effects of Ginkgo biloba on mental functioning in healthy volunteers. Arch Med Res. 2003; 34(5):373-381.

[18] Kleijnen J, Knipschild P. Ginkgo biloba for cerebral insufficiency. Br J Clin Pharmacol. 1992 Oct; 34(4):352-358.

[19] Lebars PL, et al. Ginkgo biloba for dementia. Journal of the American Medical Association 1997; 278:1327-1332.

[20] Donfrancesco R, Ferrante L. Ginkgo biloba in dyslexia: a pilot study. Phytomedicine. 2007 Jun; 14(6):367-370.