Ginkgo Biloba

What is Ginkgo Biloba?

Ginkgo biloba is one of the oldest living tree species, with a history stretching back over 200 million years. Native to China, this ancient tree has survived major extinction events and remains virtually unchanged from its prehistoric form. Traditional Chinese medicine has used ginkgo leaves for centuries to treat various ailments, but modern research focuses on a standardized extract called EGb 761, which contains specific concentrations of active compounds.

How Ginkgo Biloba works

The therapeutic effects of ginkgo come from two main classes of compounds: flavone glycosides (including quercetin, kaempferol, and isorhamnetin) and terpene lactones (ginkgolides and bilobalide). These compounds work through multiple mechanisms that support brain health and circulation. Flavone glycosides act as antioxidants, scavenging free radicals and reducing oxidative stress in neural tissue ^[1]. Terpene lactones, particularly ginkgolide B, inhibit platelet-activating factor (PAF), a compound involved in blood clotting and inflammatory responses ^[2].

Ginkgo also improves cerebral blood flow by promoting vasodilation and enhancing microcirculation. This increased blood flow delivers more oxygen and glucose to brain cells, supporting energy metabolism and cognitive function. Additionally, ginkgo has been shown to modulate neurotransmitter systems, including acetylcholine, which plays a key role in memory and learning.

Cognitive benefits and memory support

Research on ginkgo for cognitive enhancement has produced mixed but generally promising results. A comprehensive review of clinical trials found that standardized ginkgo extract EGb 761 can improve cognitive function, activities of daily living, and overall clinical assessment in patients with mild cognitive impairment and dementia ^[1]. The effects appear most pronounced in individuals over 50 who already show signs of cognitive decline.

A 24-week randomized controlled trial demonstrated that participants taking 240mg of EGb 761 daily showed significant improvements in memory recall and cognitive processing speed compared to placebo groups ^[2]. However, studies examining ginkgo for preventing dementia in healthy older adults have been less conclusive. The largest prevention trial, with over 3,000 participants, found no significant reduction in dementia incidence after six years of supplementation ^[3].

Circulation and peripheral arterial disease

Beyond cognitive benefits, ginkgo has demonstrated effectiveness for improving peripheral circulation. The same mechanisms that enhance cerebral blood flow—vasodilation and reduced blood viscosity—benefit blood flow throughout the body. Clinical studies show that ginkgo supplementation can reduce symptoms of intermittent claudication, a condition causing leg pain during walking due to poor circulation ^[4].

Patients with peripheral arterial disease taking ginkgo extract showed increased walking distance before experiencing pain, with effects comparable to some prescription medications but with fewer side effects. The improved circulation also benefits individuals with cold hands and feet, though evidence for this application remains more anecdotal than clinical.

Antioxidant and neuroprotective effects

Ginkgo's antioxidant properties extend beyond general free radical scavenging. The flavonoids in ginkgo protect neurons from oxidative damage associated with aging and neurodegenerative diseases. Research suggests these compounds may help preserve mitochondrial function in brain cells, supporting energy production and cellular health. While promising, most neuroprotection studies have been conducted in cell cultures or animal models, and human clinical data remains limited.

Dosage and standardization

The most clinically studied formulation is the standardized extract EGb 761, which contains 24% flavone glycosides and 6% terpene lactones. Effective doses range from 120mg to 240mg daily, typically divided into two or three administrations. Lower doses (120mg) may suffice for general cognitive support, while higher doses (240mg) are often used for more significant cognitive impairment or circulation issues.

It is important to choose supplements that specify EGb 761 or an equivalent standardized extract, as the concentration of active compounds in non-standardized products can vary dramatically. Effects typically become noticeable after 4 to 6 weeks of consistent use, with maximum benefits often requiring 12 weeks or longer.

Safety considerations and interactions

Ginkgo biloba is generally well-tolerated, with side effects occurring in less than 2% of users. The most common adverse effects include mild gastrointestinal upset, headache, and dizziness. However, ginkgo's blood-thinning properties warrant caution for certain individuals. The extract can increase bleeding risk, particularly when combined with anticoagulant medications such as warfarin, aspirin, or clopidogrel.

People scheduled for surgery should discontinue ginkgo at least two weeks before the procedure to minimize bleeding complications. Additionally, individuals with bleeding disorders or those taking multiple medications that affect blood clotting should consult their healthcare provider before starting ginkgo supplementation. Pregnant and breastfeeding women should avoid ginkgo due to insufficient safety data.