What Are the Benefits of Quercetin?

By Bryan Cohen

The plant pigment and bioflavonoid quercetin has been touted as an extremely beneficial supplement in recent years. Quercetin has been connected to potentially curing ailments and improving health when consumed in natural forms like blackberries and green leafy vegetables and when taken in the form of a vitamin. When taken in supplemental form, quercetin is recommended in a 400-mg dose, two to three times a day. Consult your physician before adding any new supplement to your diet.

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Benefits of quercetin

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Athletic Ability

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A preliminary study by the University of South Carolina showed that taking quercetin twice a day improved endurance and oxygen capacity in active but untrained men and women. Other studies at the University of Pepperdine and Appalachian State University have shown similar results. This improvement in athletic ability is thought to be because quercetin has a positive effect on the energy processors of the cell, the mitochondria. This positive effect, plus the activity of quercetin as a sort of antioxidant (like vitamin C), boosts the immune system and may lead to a general improvement in health.

Improve Arthritis

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Quercetin acts similarly to an anti-inflammatory drug like ibuprofen, which makes it a strong help for those suffering from arthritis. It is thought that quercetin may limit the swelling and pain that occurs in joints as a result of arthritis. According to the University of Maryland Medical Center, there are reports that a diet changed from the typical Western diet to one more centered on fruits and vegetables that contain quercetin, has improved symptoms of arthritis. That being said, the reports also point out that there is no direct evidence that quercetin supplements will improve symptoms.

Limit Eye Disorders

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Eye exam

Many eye disorders like macular degeneration and cataracts are in some part caused by free radicals in the body--particles that can cause cell damage. Since quercetin acts like an antioxidant, which helps to stop free radicals from damaging the cells, taking it in the form of blueberries, blackberries and dark cherries may help to limit eye problems. According to Herbs 2000, studies have shown that quercetin can limit the progression of cataracts in animals.

Heart Disease Prevention

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Blood test

Quercetin, when combined with the other bioflavonoids resveratrol and catechins, may help to lower the levels of bad (LDL) cholesterol which would lead to a reduced chance of heart disease. Atherosclerosis, the buildup of arterial cholesterol, may be reduced by ingesting these bioflavonoids which can all be found in red wine or supplements. Quercetin may strengthen the body against the damage that LDL cholesterol can cause while lowering your overall cholesterol level. Studies are still being conducted to prove these initial findings, but if true, this lowering of cholesterol would lead to less heart disease.

Cancer Prevention

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Fruit and vegetables

Bioflavonoids like quercetin have been connected to potential anticancer properties. According to the University of Maryland Medical Center, early studies have shown that quercetin may limit the growth of cancer cells related to prostate, breast, colon, lung, endometrial and ovarian tumors. It is thought that the action of quercetin on cancer involves limiting a certain protein that causes tumors to develop. While further studies are needed, it is prevailing opinion that those who consume more fruits and vegetables (like those that contain quercetin) have less incidence of cancer.