Ginkgo preparations in Alzheimers without effect?
Ginkgo preparations dominate the market of herbal medicine. And that’s not surprising. Until today, the rumors persist that ginkgo helps with Alzheimers or can prevent it. And this, despite the fact that there are loud voices from scientists, who have been warning against these preparations for years. Not only the effect has never been proven, but ginkgo can also have significant side effects. Despite that, many people take these preparations out of sheer desperation and often without consulting their doctor first.
What is the situation of the studies on Ginkgo extracts in Alzheimers dementia?
Several large-scale studies have already been carried out to prove the effectiveness of ginkgo extracts in dementia. The studies described here used EGb 761®, a special extract from the company Schwabe, which is the basis of the best-known ginkgo medicinal product on the market: Tebonin®.
Initially, the results pointed in the right direction. In a small-scale study from the 90s with only 20 participants, a positive effect on the progression of the disease was found after three months. Since studies with such a small number of participants are of limited informative value, two large-scale studies were carried out in the following years. The result: The Ginkgo biloba extract (EGb 761®) shows no significant effect on Alzheimers dementia.
The first large-scale study is a randomized, placebo-controlled, double-blind study. This means that neither the doctor nor the patient know whether they are administering or receiving a placebo or a potentially effective preparation. The 3,069 patients had little or no cognitive impairment and were observed over an average of six years.
The second large-scale study examined 2,854 patients over 70 years old, who had visited their doctor because of decreasing memory performance. In neither of the two studies was the ginkgo extract able to preventively influence the appearance or progression of cognitive impairments. It simply showed no clinically significant effect.
For older users with previous cardiovascular diseases, the Ginkgo biloba extract could even mean an increased risk of dementia according to an exploratory study.
– Specialist journal Arznei-Telegramm
Misleading advertising for Ginkgo preparations
Probably no other plant is as well known to us from advertising as Ginkgo biloba. Older people, who misplace their keys or talk about memory problems in old age, go usually hand in hand with the advertisement of a Ginkgo preparation. The constant presence of this type of advertising is not surprising considering that the Ginkgo biloba extract market was valued at around 240 Million USD in 2020. Thus, a lot of money is made with the ginkgo myth.
The company Schwabe initially openly advertised its own food supplement with ginkgo as a remedy against Alzheimers, until the Regional Court of Cologne prohibited this approach (decision of November 6, 2015 – 6 U 65/15). The company is no longer allowed to make statements like “Carefree without fear of Alzheimers and dementia?” or “Turn your biological clock 10, 15 years back. Only one capsule per day is enough! “ and many more like these.
Nevertheless, the current packaging of Tebonin® konzent® also advertises the use of the preparation “to improve an age-related deterioration in mental abilities and the quality of life with mild dementia”, while Tebonin® intens is supposed to be a “plant-based active ingredient to improve the performance of the brain and blood circulation”. In view of the already described study situation with two large-scale, methodologically correct studies that show no effect, this approach is very questionable.
Ginkgo preparations can double the risk of stroke
Even if ginkgo is now widely known, the side effects of these preparations are not. According to the package leaflet of Tebonin®, headaches are very common. However, drowsiness or dizziness, diarrhea, pelvic pain, nausea and vomiting are often among the symptoms that appear.
Even the genotype can be damaged when taking ginkgo. This is due to occasionally high proportion of ginkgolic acids. This proportion is monitored for medicinal products containing ginkgo, but not for dietary supplements.
Therefore, the consumer advice center warns against taking food supplements with ginkgo, as the ginkgolic acid values are not checked. She writes: “Ginkgolic acids can cause allergies and gastritis and contain cell and nerve toxins. A mutagenic effect has also been detected”.
Ginkgo extracts can also inhibit or activate certain metabolic enzymes and proteins. Therefore, there may be interactions with other drugs. Patients with cardiovascular diseases, who take anticoagulants or antihypertensive drugs, should be particularly careful because ginkgo increases the bleeding tendency.
The specialist journal Arznei-Telegramm also warns against the increase of the risk for strokes, which can double with the use of ginkgo preparations.
According to the current level of knowledge, all medical studies properly carried out with a total of more than 6,000 patients, show no effect of the ginkgo extract EGb 761® / Tebonin® in the prevention or treatment of Alzheimers dementia. Nevertheless, it is still widely advertised that ginkgo preparations have an influence on the progression of Alzheimers dementia and could even be taken for prevention.
However, ginkgo preparations carry the risk of significant side effects. Therefore, you should urgently discuss the use of such medicinal product with an attending physician. However, it is best to refrain completely from taking it, as there are herbal alternatives that have no or significantly less side effects than ginkgo preparations.
At this point, we would like to draw attention to the excellent article “Gentle cure for the brain?” by Cornelia Stolze at alzheimerpunkt.ch, which also deals with the topic of ginkgo.