Quercetin

Quercitin is one of many flavinoids found in plant pigments. It's chemical name is 2-(3,4-dihydroxyphenyl)-3,5,7-trihydroxy-4H-chromen-4-one

Other names include: Citrus bioflavonoid, Sophoretin; Meletin; Quercetine; Xanthaurine; Quercetol; Quercitin; Quertine; Flavin.

Function
Quercitin has antioxidant and anti-inflammatory effects.

Health Uses
Quercetin supplements have been promoted for prevention and treatment of cancer. However, there is "...no reliable clinical evidence that quercetin can prevent or treat cancer in humans".[2] It also is promoted for atherosclerosis, high cholesterol, heart disease and circulatory problems. People with diabetes, hay fever, cataracts, peptic ulcer, schizophrenia, inflammatory conditions (asthma, gout), chronic fatigue syndrome and chronic prostate infection. Quercitin is also used by athletes to increase indurance and improve performance.

Safety
The US FDA has issued warning letters,[39] e.g., to emphasize that quercetin is not a defined nutrient nor an antioxidant, cannot be assigned a dietary content level and is not regulated as a drug to treat any human disease. The European Food Safety Authority evaluated possible health claims associated with consumption of quercetin, and found that no cause-and-effect relationship has been established for any physiological effect in human health or diseases.[5]