Quercetin Dihydrate

Quercetin is a naturally occurring compound that is part of a larger category of substances referred to as flavonoids. The chemical name for quercetin is 3,3'4',5,7-pentahydroxy flavone. Flavonoids tend to be yellow in color and more frequently occur as glycosides (linked to a sugar moiety) in nature. Quercetin is the aglycone (the non-sugar part) portion of a number of flavonoids, including rutin, quercetrin, isoquercetrin and hyperoside. [1]

Quercetin may possess potent anticancer and anti-inflammatory activities. Anti-inflammatory activity is likely due to quercetin's ability to inhibit lipoxygenase and leukotriene B4, both of which are part of the inflammatory cascade. [2] As well, it inhibits histamine release from mast cells which is the basis of allergic reactions. [3]

Additionally, quercetin has demonstrated the ability to prevent oxidative stress, and to inhibit NF-kappaB activation in an experimental model of portal hypertensive gastropathy. [4] It also has the ability to constrain IL-12 signaling and Th1 differentiation, which may indicate its potential as a therapeutic agent for multiple sclerosis and other Th1 cell-mediated autoimmune diseases. [5] Quercetin is a potent inhibitor of tyrosine kinase, an important enzyme in tumor development, as well.

Quercetin Food Sources

Quercetin is found in a variety of foods and botanicals. Food sources high in quercetin include allium family vegetables, brassica family vegetables, and apples. Hypericum perforatum, Gingko biloba, Sanguinaria canadensis, and Camellia sinensis contain significant amounts of this flavonoid. [1] Black currants, lingonberries and bilberries are also considered good sources of bioavailable quercetin. [6] Interestingly, quercetin from rutin has been shown to be more bioavailable in women than in men. [7]

Products Containing Quercetin Dihydrate
Name Price Rating Serving Price # of Servings Manufacturer Health Condition
Joint Fuel $29.12
$0.73 40 Twinlab Osteoarthritis


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