Quercetin is a beneficial chemical compound widely dispersed in the human diet, present in foods such as apples, tea and various other fruits and vegetables. Studies connecting quercetin and cancer show that the beneficial compound may play a role in preventing cancer cells from growing, indicating its possible use in future cancer treatment. The exact mechanism behind cancer prevention with quercetin is unknown, yet most researchers indicate that the compound's anti-inflammatory and antioxidant properties may be responsible for the beneficial effects. Although the link between quercetin and cancer have been established in controlled scientific settings, the effects on treatment for cancer in humans are currently unknown.
In human nutrition, compounds called polyphenols make up the common class of antioxidants essential for combating free radicals that pose a danger to human health. Free radicals have been associated with cancer in some studies, leading many researchers to believe that antioxidants are important for preventing life-threatening diseases. A common polyphenol in the diet is quercetin, found in tea, apples and a wide variety of other fruits as well as vegetables. In animal studies as well as cell isolation studies by many nutrition and health experts, a link between quercetin and cancer prevention has been proposed.
Using animal models, as well as controlled cell isolation studies, the quercetin compound has shown to help combat cancer cells and promote their death. This is often called apoptosis, and generally refers to a cell that kills itself to prevent further mutations that might contribute to cancer or other diseases. It has been proposed in studies that link quercetin and cancer that the polyphenol may act as a powerful antioxidant on these cancer cells, preventing their growth. Other factors that may be present in the antioxidant may also be contributing to fulfilling apoptosis, yet more conclusive studies must confirm this theory.
Some scientists theorize that the effects of quercetin and cancer prevention may come down to not only the antioxidant benefits but the anti-inflammatory benefits as well. Due to the fact that some studies indicate that inflammation has been associated with development of cancer, many researchers believe that the anti-inflammatory compounds in quercetin contribute to cancer prevention. It is unknown as to the effects of quercetin therapy on humans or its effectiveness when injected or taken by mouth. Most doctors and nutritionists advocate the consumption of quercetin-rich foods, like apples and tea, as the best quercetin strategy until safe supplements or medicines are developed.
