origin

Quercetin is one of the secondary plant substances (phytamines). Secondary plant substances exist in a wide variety of chemical structures, each with specific properties. The best-known groups of secondary plant substances include polyphenols, isoflavones, and carotenoids. Quercetin belongs to the group of polyphenols and to their subgroup, the (bio)flavonoids. There are over 5,000 different types of bioflavonoids that occur naturally in plants. They are responsible for flower and leaf color in plants, as well as for protection against UV radiation, predators, viruses, fungi, and bacteria. Quercetin is the most common flavonoid, and it can be used to synthesize other flavonoids.

Quercetin is absorbed into the body via the (v.a. small intestine into the blood. According to current studies, slightly less than half of the consumed amount is absorbed by the body, and it takes up to nine hours after ingestion for the quercetin to become available to the body. The body does not store quercetin permanently, but excretes it after approximately 35 hours. Therefore, quercetin should be administered regularly as part of a therapy.

Happen

A high quercetin content can be found, for example, in capers (about 1600 mg quercetin per kg), onions (about 284-486 mg quercetin per kg), chives (245 mg), cranberries (156 mg), black currants (69 mg) and kale (60 mg).

Quercetin is included v.a. in the outer shells or layers of plants (e.g. in tree bark) and fruits (e.g. in grapes, apples, onions) to protect them from free radicals. This also means, of course, that almost no quercetin is absorbed if the outer skins are removed before consumption. For example, quince skins can contain up to 180 mg of quercetin per kg. In the fruiting body itself, however, hardly any relevant amounts of quercetin are found. However, only minimal amounts can be found inside. In onions, too, around 20% of the quercetin is found directly under the skin and is therefore usually removed when peeling.

Also the Cultivation method is relevant for the quercetin contentFor example, organically grown tomatoes contain approximately 80% more quercetin than conventionally grown tomatoes. Furthermore, heat during cooking can cause further quercetin losses (according to studies, up to 25%).

Under the tree bark v.a. that of the oak in terms of quercetin content, which also gives rise to the name “quercetin” - because “quercus"" is the Latin name for "oak"; more specifically, for the dyer's oak (Quercus velutina). However, very high quercetin levels have also been found in the bark of other tree species over time. QIDOSHA Quercetin is extracted from the Japanese pagoda tree (Sophora japonica), as its flower extract contains particularly high levels of natural quercetin.

Benefits and mode of action

Since to date hardly any scientific studies on quercetin in humans are so-called “health claims”, d.h. Health claims associated with taking the drug are inadmissible. The study therefore refers v.a. on laboratory and animal testing. However, since there are numerous promising starting points in this area, clinical trials in humans are expected in the near future.

It is undisputed that quercetin is a particularly powerful antioxidant It appears to be comparable to OPC or epigallocatechin gallate (EGCG) from green tea leaves. The reason for this lies in the chemical structure of quercetin – it is a polyphenol that has an additional hydroxyl group instead of a sugar molecule.And the more OH groups a polyphenol has, the higher its antioxidant effect.

Another Special features of flavonoids like quercetin lies in its ability to regenerate already oxidized substances (e.g. vitamins C and E), d.h. them their restore antioxidant power.

In one Meta-study from 2019 to Effect of quercetin on diabetes Based on animal studies, researchers were able to find that there was a significant difference between the mean serum glucose levels when doses of 10, 25 and 50 mg of quercetin per kg of body weight were administered. https://pubmed.ncbi.nlm.nih.gov/30735748/

One Japanese study suggests that quercetin have an anti-allergic effect by inhibiting the so-called histamine H1 receptor (H1R). The severity of allergy symptoms increases proportionally to the activity of this receptor. https://pubmed.ncbi.nlm.nih.gov/23333628/

One Study by the University of Naples postulates a anti-inflammatory effect Quercetin, in principle, has the ability to reduce concentrations of the tissue hormone prostaglandin E2 and the fatty acid derivative leukotriene B4. Both substances are relevant for the initiation of inflammatory processes and play a key role in the release of inflammatory mediators such as histamine. https://onlinelibrary.wiley.com/doi/abs/10.1111/j.2042-7158.1988.tb05250.x

One Study from 2007 blood pressure lowering effect The subjects were given 730 mg of quercetin daily for almost a month, and a reduction in systolic (−7 ± 2 mm Hg) and diastolic (−5 ± 2 mm Hg) blood pressure was observed in patients with hypertension. Further clinical studies are therefore recommended. https://pubmed.ncbi.nlm.nih.gov/17951477/

How do I recognize a high-quality product?

When purchasing, you should make sure the product is 100% natural. The premium flower extract should come from the Japanese pagoda tree (Sophora japonica) and ideally have an extract ratio of 15:1. The water-alcohol extract used in production should be highly pure and contain no chemical solvents. Capsules are a perfect dietary supplement for your daily routine.

Legal consumer information

German and European law aims to protect consumers from supposedly misleading claims of effectiveness. The statements made here refer to the original Ayurvedic and TCM texts. This ancient knowledge is based on experience passed down from generation to generation. It is not intended to claim that the products described here have an effect in the sense of Western medicine. All products are dietary supplements; they are not medications and have no medical effect. If you are ill and require medical care, please consult your doctor or pharmacist.