The Effects Of Quercetin On The Human Body Biology Essay

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Quercetin is a type of plant-based chemical, or phytochemical, known as a flavonoid (also Phytochemicals). Sources of quercetin include the commonly found apples, red onions, tea leaves, wines, and other related foods. The quercitin can also be found as a supplement for diet. The substance has been found to raise the energy spending in mice, but this lasts only for a short period of less than eight weeks. The effects of the substance on tolerance to exercise in rats have been related to the enhanced mitochondrial biogenesis. The substance also is said to be the aglycone form of numerous other flavonoid, like quercitrin and rutin which found mostly in buckwheat, citrus fruit and onions. Quercetin forms the quercitrin, glycosides and rhamnose together with rutinose and rutin, respectively. Quercetin is in the class of IARC group 3 (with no tangible evidence of carcinogenicity in humans).

Overview of quercetin

It appears to consist of anti inflammatory and elements of antioxidant effects. Quercetin has been found to be more effective against a broad range of diseases especially cancer. Some early quercetin laboratory analysis appears to be promising but as per now there is no clinical evidence that is sufficient enough that substance can treat or prevent cancer in human beings. The substance is known to have various uses, however, most of the uses are depends on the early analysis mainly from laboratory related studies. Some of the initial studies have shown that quercetin has got an antihistamine effects and is in most cases promoted to assist in the control of allergies and also asthma. Some studies also indicate that it can assist in stabilizing small vessels of blood and may also assist in protecting against heart diseases and stroke. Quercetin sometimes is promoted to assist in preventing or treating various kinds of cancer. It has promoted also to assist with the signs and symptoms of prostatitis which is chronic that is the swelling of prostate glands and to subject some neurological complications related to diabetes.

Constituents of quercetin

Quercetin is a common chemical pigment in the rinds and barks of a wide variety of plants. Quercetin is one of the major flavonoids in the human diet, and can be found in high quantities in skins of apples, the red onions and also in red wine. Also it is found in the leafy green vegetables like berries and also in herbs for example ginkgo and the famous St. John's wort. The substance is also available in greater amounts in supplements for human diet compared to that which would be found typically in foods. These supplements are usually sold as tablets and or capsules ranging from 50-500 milligrams in a single dose. Categorically there is no single standard dose which recommended for quercetin.

History of quercetin

Plants containing flavonoids have a long history of use in traditional medicines in many cultures, but flavonoids themselves were not discovered until the 1930s. Quercetin first attracted attention a number of past decades from where it was found to result to mutations of DNA in bacteria, an indication that may contribute to cancer in human bodies. Since that time the animal research has been less conclusive, and the scanty evidence present in human beings is almost against the idea. General research in current years has since been focusing on various possible assisting effects of this substance which includes its potential key function in the prevention of cancer.

Effects of quercetin on human body

Most of the research on quercetin and cancer has been done in cell culture or animal studies. The studies on querccetin suggest some possible beneficial effects; however the studies do not give proof that the effects can be also achieved in human bodies. Still it is not clear how sufficient quercetin can be absorbed in human body especially when it is taken through the mouth. Some clinical controlled trials are required to indicate if quercetin has a beneficial effect in the human body. Studies conducted in cell cultures shows that the substance has activities which are against some various cells for cancer. This can be as a result of its antioxidant, anti-inflammatory effects and also as a result of any other possible mechanisms. Current laboratory studies show that the substance can slow down the multiplication of cancer cells and can assist in fostering apoptosis which is a kind of cell death that is natural in nature and does not occur in many of the cancer cells. Several laboratory researches in different animals have indicated that the substance may assist in protecting the body against various forms of cancer cells and most probably the colon cancer.

Laboratory researches in human bodies have been mainly based on population and have been focusing on the importance of flavonoids as a group in the human diet with disregard to quercetin (substance) in particular. Such like studies are not usually as conclusive and comprehensive as the clinical trials. This is simply they cannot be in a position to prove the cause and also the effect but in most cases suggest linkages that can therefore further be tested in laboratory clinical type of trials. On the other hand some of these studies which are based solely on population have indicated that individuals with high content flavonoids in their diets can have a lower risk of lung, breast pancreatic and other forms of cancer, but it isn’t clear concerning the importance of quercetin in such results. A clinical research on people who have a high tendency of inheriting the development of colon cancer indicated that combination both curcumin and quercetin food supplements reduces the size and number of the precancerous tumors of the rectum. There is no other related clinical study or testing which indicates the possibility of quercetin in preventing or treating cancer has been included in the literature for medical studies. More clinical testing and trials are required to further investigate and therefore clarify the possible benefits of the substance.

In addition to the ability of quercetin to treat and or prevent the likelihood of cancer in human beings, fundamental studies and research have also indicated the possibility of a potential value for the substance in inflamed prostate (prostatitis) and also the likelihood of heart disease. However, more clinical studies are required before any potential recommendations are categorically released. Before any conclusive and comprehensive clinical research and study findings are suggested, it is advisable and reasonable to incorporate foods rich in quercetin to be a component of balanced diet for human beings with a strong emphasis on vegetables, fruits, whole grains and legumes. The relationship between such phytochemicals and the other related compounds in the food substances is not clearly understood, however it is not likely that any of these single substances offers an excellent protection and or treatment against cancer. A diet which is balanced and that which comprises of five or more than five servings per day of vegetables and fruits, along with other foods from different types of other related plant sources like nuts, grain cereals, seeds and beans, is possible to be more sufficient and effective in reduction of the risk of cancer compared to just eating large quantities of a single phytochemical.


Quercetin in the amounts consumed in a healthy diet is unlikely to cause any major problems. Some occasional clinical reports have indicated cases of nausea and vomiting when food supplements consisting of quercetin are usually taken in considerably high doses. The quercetin food supplements have not been thoroughly studied for the health safety of women who are expectant and or breast-feeding their babies. This implies that depending on only this kind of treatment and prevention and on the other hand delaying or avoiding the conventional medical protocol of care for the cancer patients may bring serious health and safety consequences.