Ginkgo biloba is a substance used in medicine for over 1000 years and is currently one of the herbal medicines commonly used in the world due to its antioxidant action and its alleged benefits in treating memory problems, lack of energy, lack of concentration, impotence sexual, among others.
Unfortunately, the fact that a substance is widely used for centuries does not guarantee that it is really effective against everything as advertised, or that it is free of side effects and contraindications. Therefore, the aim of this paper is to address the ginkgo biloba in a scientific way, showing what the studies proved to be true, what is myth and what is not yet fully understood from a scientific point of view.
The ginkgo biloba extract is a substance obtained from the leaves of the Ginkgo tree, native of Korea, China and Japan, but now present throughout the world, including in large Brazilian cities. The ginkgo tree can exceed 40 meters and live more than 1,000 years.
The ginkgo biloba extract is currently one of the 10 medicinal herbs commonly used worldwide. This herbal medicine has two active substances which are responsible for its effects on our body: flavonoids and terpenes.
Ginkgo biloba is a aclamadamente substance beneficial for the brain functions, but its real effectiveness in the treatment of cognitive disorders is not yet fully understood. This does not mean, however, that various effects and brain ginkgo biloba actions have not been unveiled.
Studies in animals and humans have shown that the drug acts directly on neurotransmitters and offers protection to neurons by different mechanisms. Ginkgo biloba has proven antioxidant activity, it causes vasodilation of cerebral blood vessels, increasing blood perfusion in the brain, prevents clot formation and optimizes the use of glucose by the brain.
These and other actions already recognized drug provide the theoretical basis for use of ginkgo biloba in treating various neurological diseases. However, modern medicine is evidence-based. Do not just be a theoretical basis behind the treatments, we must prove that these actions are in practice effective against diseases. It is because ginkgo biloba increases blood perfusion in the brain and prevents clots we can say that it is effective in the prevention and treatment of stroke, for example. Often, a drug has a strong theoretical basis, but when we go to practice, its use does not show any beneficial effect in the treatment of diseases that supposedly they would be effective.
So do not just ginkgo biloba have different actions supposedly beneficial in the brain. So its use is indicated for the treatment and prevention of diseases, it needs to prove that it really brings real benefits to the patient. Therefore, it is important to study drug separately for each disease.
Let's talk briefly about some diseases for which the use of ginkgo biloba has been relatively well studied.
Ginkgo biloba in the treatment of Alzheimer's disease and other dementias
Despite some isolated studies showing little cognitive improvement in Alzheimer's patients who used Ginkgo biloba for at least 6 months, a major review conducted in 2007 of 35 studies concluded that previous studies had methodological flaws and had studied very groups Note patients. The conclusion of this systematic review of the main studies was that there is not enough data to say that Ginkgo biloba is superior to placebo in the treatment of Alzheimer's. When compared to drugs commonly used to treat dementia, ginkgo biloba has inferior results.
Another study published in 2008 that followed for 8 years, more than 3000 elderly showed that daily use of ginkgo biloba showed no evidence that the drug is superior to placebo in preventing dementia. Therefore, there is no scientific evidence to support the use of ginkgo biloba for treatment or prevention of dementia.
Ginkgo biloba for memory loss and concentration problems
Historically ginkgo biloba has always been indicated as a good treatment to improve memory, concentration and the degree of attention, especially in the elderly. Unfortunately, studies have also shown that the drug is not superior to placebo in these cases. There is, therefore, no scientific evidence to indicate ginkgo biloba to improve the memory of elderly patients.
Diseases that seem to respond to the use of ginkgo biloba
Despite the disappointment with the lack of efficacy of ginkgo biloba in treating dementia, the memory loss and other cognitive functions of the elderly, there are a number of problems that seem to improve with the use of the extract. Among those who have scientific studies confirming positive results include:
Circulatory problems of members lower (small effectiveness, only slightly higher than placebo)
In general, ginkgo biloba not shown, the light of scientific studies as a drug with great efficacy in the treatment of any significant disease. In most cases, the efficacy is only slightly superior to placebo.
On the other hand, a lower rate of side effects and potential benefit, even if it takes in some cases, make their use is indicated for some patients.
Ginkgo biloba is a drug with very low rate of adverse effects. When these occur are usually nausea, abdominal pain, diarrhea or headache.
However, the inhibitory action on platelets might increase the risk of bleeding in some situations. The drug should not be used in patients with high risk of bleeding. Following the same logic, in patients who will undergo surgical procedures, it is suggested to ginkgo biloba suspension at least 36 hours before the operation.
Ginkgo biloba can increase the risk of bleeding when used concomitantly with other drugs acting on platelets and other coagulation factors, such as aspirin, nonsteroidal anti-inflammatory drug, heparin or warfarin.
Due to lack of clinical studies in pregnant proving their safety, currently not recommended the use of ginkgo biloba during pregnancy or lactation.
Patients with a history of seizures or epilepsy should also avoid the use of ginkgo biloba as there are sporadic reports that the drug may facilitate the occurrence of epileptic seizures. There is also the possibility of ginkgo biloba interact and reduce the effects of anticonvulsants.
No evidence that ginkgo biloba interact with the effects of the contraceptive pill.
Most studies on ginkgo extract used the standard form of Ginkgo biloba EGb 761, which contains 24% of flavonoids and 6% terpenoids. Typical dosages of Ginkgo biloba EGb 761 used in studies and recommended by manufacturers is 40 mg three times daily or 60 to 80 mg twice per day.
Studies show that daily use for over a year is not associated with any serious security problem.