In my first book (Live Young, Longer), I introduced Ginkgo biloba as one of the important ingredients to consider for healthy longevity. At the time, I could not mention that we had also discovered new modulators of primary aging during our research with Concordia University. These findings are now published in a scientific journal with a high impact in basic research on primary aging, where patents have been filed. I will therefore be able to make the link between our research with the well-demonstrated health benefits of ginkgo biloba and its relevance in an aging context.

Let’s talk about quality above all

When talking about the health benefits of plants and plant extracts, it is always very important to talk about the quality of the raw material, especially in the case of ginkgo biloba. It is considered to be the most counterfeit ingredient, exhibiting the highest rates of adulteration on the market. It could be the addition of external substances, the presence of contaminants, the use of the wrong plant, or even the wrong part of the plant. Often, even the manufacturer is not aware of the presence of an adulterated ingredient. Several scientific studies have shown irregularities in the concentration of standardized extracts marketed. For example, one review reported that out of 29 extracts tested, only four contained exactly the doses mentioned (25 were wrong; 86%).

For ginkgo biloba, the active ingredients are extracted from the leaf. They are polyphenols from the group of flavone glycosides, terpene lactones, and proanthocyanidins. The most abundant are the flavone glycosides, including quercetin and catechin. Lactone terpenes contain molecules unique to Ginkgo biloba, called ginkolides. Terpenoids, flavonoids and anthocyanidins are known to be the active elements of this plant. Quality extracts are standardized at 24% flavonoids and 6% terpenoids.

The problems with adulteration are very complex. For example, one of the flavones in ginkgo biloba is rutin. The cheapest source of rutin on the market is buckwheat (Fagopyrum esculentum M). This allows an extract producer to add enough buckwheat extracts to their product to obtain 24% flavonoids. Will this product have the same properties as ginkgo biloba? Probably not. The profile obtained by HPLC (high performance liquid chromatography) analysis will be practically the same! Soy isoflavones can also be used to defeat this standardization. The large variation in composition and quality of extracts could also explain the variability of clinical results reported in the literature.

For example, several meta-analyzes have concluded that ginkgo biloba extracts are ineffective for tinnitus. Yet a meta-analysis, published in 2011, concluded that there is an obvious significant effect for tinnitus. These are standardized extracts of ginkgo biloba. The study specifically highlights the effectiveness of EGb 761® extract. The author mentioned that the two important factors are the quality of the studies considered and the quality of the extracts. The excerpts are not all created equal. As another example, if taking a ginkgo biloba product causes skin reactions such as rash or headache, the product probably contains ginkgolic acid and is therefore of poor quality. You should no longer consume it.

From yesterday to today

Ginkgo biloba is a large tree referred to as a living fossil because it is the last unchanged representative of a family of trees that became extinct more than 300 million years ago. Dinosaurs have crossed paths with ginkgoaceae. It can live more than 1000 years and reach 40 meters in height. The leaf is used mainly for its antioxidant, neuroprotective, and vasodilating properties. Ginkgo biloba has been used in traditional medicine for centuries. It is one of the most widely used herbs for medicinal use around the world. A study carried out in Germany among people aged 60 to 94 reported that 66% of respondents consume dietary supplements. For ginkgo biloba, 57% of users confirmed having been recommended to use it by their doctor.

When you consider doctors and pharmacists, they account for 73% of the reasons for its use among the elderly in Germany. Obviously, this is a very clear confirmation of the positive perceptions of the German medical profession regarding the use of ginkgo biloba. The German government recognizes the use of ginkgo biloba for:

  • Loss of memory and concentration, depression, tinnitus, dizziness and headaches associated with organic brain syndrome and all forms of dementia;
  • Improving peripheral circulation in vascular occlusive syndromes, including intermittent claudication;
  • Dizziness and tinnitus of vascular origin.

Against dementia

One study (2013) compared the use of ginkgo biloba with that of piracetam, a prescription drug in the United States for dementia and cognitive impairment. This is a 20-year follow-up study in which the cognitive abilities of 3,612 people aged 65 and over were assessed.

This study showed improvement in cognitive abilities in people taking a standardized ginkgo biloba supplement (EGb 761®), while patients taking piracetam had no improvement, but rather, deterioration. However, we should not question the use of drugs in our modern medicine, but rather know that some alternatives can be just as valid if they are supported by good science. The main use of ginkgo biloba, very well supported clinically, is for memory and the prevention of cognitive decline or dementia.

Numerous studies

Ginkgo biloba remains the most studied natural product for its preventive effects on dementia. One study identified more than 1,142 scientific studies on ginkgo biloba. Considering only the highest quality clinical studies (nine studies with a total of 2,578 patients), the authors concluded that ginkgo biloba extracts are superior to placebo in preventing cognitive decline and maintaining everyday abilities. These results are significant only for the youngest participants (whose average age is less than 75 years). This last point probably underlines that in order to prevent, you have to act early enough, but that at 75, it is not too late. It is also worth mentioning that these studies usually last six months. So, a period of six months is already enough to see an improvement in cognitive abilities.

Mechanisms of action

Regarding the metabolic pathways of aging, standardized extracts of ginkgo biloba have demonstrated positive effects in yeast, nematode, and human neurons in culture. There would be an increase in the defenses against oxidation and an increase in the DNA repair capacity.

In the nematode, this beneficial effect resulted in an 8% increase in lifespan and an increase in resistance to thermal and oxidative stress by 33% and 25% respectively. A flavonoid purified from ginkgo biloba extract, tamarixetine, increases the lifespan of nematodes by 25%.

Ginkgo biloba extracts have also been shown to improve energy production by the mitochondria. This is one of the most important aspects that can reduce the negative effects of aging.

Effective doses

Serious clinical research is carried out with standardized extracts: 120 to 360 mg of an extract (average ratio 50:1; i.e., 50 times more concentrated than the original plant), titrated to 24% flavonoids and 6% terpenoids. We should aim for an average dose of 200 mg per day. Unfortunately, even standardized products often do not contain the mentioned doses or the right molecules. It is important to buy from a serious business. Beware of products containing only pulverized leaves: the dose should then reach around 10,000 mg per day!

Indications

For peripheral circulation disorders (e.g., Raynaud’s syndrome), memory problems, and to promote better concentration, especially in aging people. May decrease dizziness and hearing damage caused by poor circulation or arteriosclerosis. Hearing impairments include tinnitus, these various noises that our ears perceive, with or without the actual presence of noise.

A good quality study has shown its efficacy against anxiety disorders where mechanisms of action are known. Useful as an adjunct in the treatment of migraines, headaches and heavy legs (venous insufficiency). Can be considered for erectile dysfunction and hemorrhoids.

Other applications

In the Chinese Pharmacopoeia, ginkgo biloba is used to treat asthma, due to its inhibitory effect on platelet aggregation factors (PAF). Ginkgo biloba extract also demonstrates peripheral vasodilator, antioxidant and neuroprotective effects. These effects may explain its action on memory, especially in the presence of arteriosclerosis in the elderly. It also has effects on intermittent claudication, senile dementia and Alzheimer’s. Note that using ginkgo biloba does not necessarily prevent Alzheimer’s disease.

Cognitively, ginkgo biloba extracts may decrease plasma concentrations of corticosterone, adrenocorticotrophic hormone, norepinephrine, and epinephrine in different areas of the brain. Stress and anxiety cause an increase in these substances in the brain. Thus, taking ginkgo biloba may reduce the harmful effects of stress and anxiety.

Possible drug interactions

Ginkgolides have agonist effects on platelet-activating factor (PAF) receptors. These PAF molecules have the function of causing inflammatory reactions and/or platelet aggregation (blood clotting). This biological activity is linked to the physiological benefits of Ginkgo biloba, but it modifies the effectiveness of anticoagulant drugs and therefore causes an interaction that could be harmful. Although the dose that could be problematic is not yet clearly established, and may not be reached with the use of common supplements, it is recommended that you refrain from taking supplements containing ginkgo biloba if you are taking blood thinning medications.

 

Originally published in the Vitalité QC magazine: https://vitalitequebec-magazine.com/en/home/ 

 

References:

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