Flavonols are found in plant-based foods with onions, apples, berries, kale, cacao, and broccoli having the highest concentrations.
Vopr Pitan. 2013. Biologically active substances of plant origin. Flavonols and flavones: prevalence, dietary sources and consumption. Flavonoids are the most numerous group of natural polyphenolic compounds, the secondary metabolites of plants that may play an important role in human health protection. Flavonols and flavones constitute the main two classes of flavonoids, whose antioxidant properties and high biological activity have been proofed both in vitro and in vivo. This review summarizes data, concerning the structure, occurrence and content of the main flavonols (quercetin, kaempherol, myricetin, isorhamnetin) and flavones (apigenin, luteolin) in some most widely consumed foodstuffs, including vegetables, fruits, berries, nuts, beverages and other products of plant origin.
Epidemiological studies suggest that a high dietary intake of flavanols, a subclass of flavonoids, is associated with reduced risk of vascular disease. Clinical studies have also shown that the consumption of certain flavanol-rich foods (e.g., cocoa, tea, red wine), as well as intake of the individual flavanol epicatechin, can result in improvement in a number of parameters associated with vascular disease, including improved endothelial function, reduced platelet reactivity, and reduced oxidative stress.
Some of the common flavonols include:
Fisetin is a natural flavonol found in edible vegetables, fruits, and wine.
Quercetin is one of the most widely found flavonols in fruits and vegetables consumed by humans.
Not so common flavonols are:
Icariin, a substance found in horny goat weed plant that has blood vessel dilation benefits.
Eyesight Rx for good vision
Unlike some vision products that provide nutrients and herbs for long term healthy eyesight support, and prevention of visual impairment, but don't seem to have much of an immediate effect on visual acuity, Eyesight Rx was formulated to provide a quick and noticeable eyesight improvement within days of use.
Reports from Eyesight Rx users indicate enhanced clarity of vision, colors being brighter, better focus, and overall improvement in close and distance vision.
Vitamin C (Ascorbic acid) is a well-known antioxidant.
(eriocitrin, hesperidin, flavonols, flavones, flavonoids, naringenin, and quercetin)
(alpha carotene, astaxanthin, beta carotene, cryptoxanthin, Lutein, Lycopene, Zeaxanthin)
Bilberry extract (Vaccinium myrtillus)
Jujube extract (Zizyphus jujube)
Ginkgo biloba (Ginkgo biloba)
Suma extract (Pfaffia paniculata)
Mucuna pruriens extract (Cowhage)
Cinnamon (Cinnamomum zeylanicum)
Lycium berry extract (Lycium Barbarum) - also known as Goji Berry
Sarsaparila (Sarsaparilla Smilax)
Alpha Lipoic acid helps with visual health
Blood Thinning Flavonols
in Chocolate and Cocoa
An increasing number of foods have been reported to have platelet-inhibitory actions, and research with a number of flavanol -rich foods, including, grape juice, cocoa and chocolate, suggests that these foods provide some protection against thrombosis. Consumption of flavanol -rich cocoa inhibit several measures of platelet activity including, epinephrine - and ADP-induced glycoprotein IIb/IIIa and P-Selectin expression, platelet microparticle formation, and epinephrine-collagen and ADP-collagen induced primary hemostasis. The epinephrine-induced inhibitory effects on GP IIb/IIIa and primary hemostasis are similar to, though less robust than those associated with the use of low dose (81 mg) aspirin. Flavanols present in cocoa and chocolate can modulate platelet function through a multitude of pathways.
Brain health and memory
A lab-created cocoa drink with a high flavonol content, created by Mars, Inc., appears to improve normal age-related memory loss, a small study suggests, Oct. 26, 2014 Nature Neuroscience.
disease, and stroke
Foods rich in flavonoids -- from apples and pears to dark chocolate and red wine -- may help shield postmenopausal women from coronary heart disease, cardiovascular disease and stroke, a new study shows. Flavonoids have been hypothesized to protect the heart by reducing levels of low-density lipoprotein or "bad" cholesterol and reducing inflammation. Dr. Pamela J. Mink of Exponent, Inc., used three newly available databases from the U.S. Department of Agriculture to determine the flavonoid contain of foods, the researchers analyzed results of food questionnaires on diet from 34,489 postmenopausal women participating in the Iowa Women's Health Study. Dr. Pamela J. Mink and colleagues specifically examined the association between the amount of flavonoids the diet and heart disease and death over a 16-year period. The new information allowed the researchers to look at both total flavonoids and seven different subclasses of the plant compound. Three subclasses of flavonoids, anthocyanidins, flavanones, and flavones, were linked to a significantly reduced risk of heart disease, blood vessel disease or cardiovascular disease mortality. Specific foods also were linked to risk reductions in heart, blood vessel disease and mortality as well, including bran, apples, pears, red wine, grapefruit, strawberries and chocolate. American Journal of Clinical Nutrition, March 2007.
Flavonols and pancreatic
Evaluation of the eating patterns of 183,000 California and Hawaii residents has found evidence that a diet high in flavonols reduces the risk for pancreatic cancer. During an average of 8 years, 529 subjects developed pancreatic cancer. People who had the largest amount of flavonols in their diet -- measured with a "food frequency" questionnaire -- had a 23-percent lower risk of developing pancreatic cancer compared with people with the lowest levels, Dr. Ute Nöthlings from the German Institute of Human Nutrition Potsdam-Rehbruecke reported at the annual meeting of the American Association for Cancer Research in Los Angeles in April 2007.
Biofactors. 2013. Flavonols enhanced production of anti-inflammatory substance(s) by Bifidobacterium adolescentis: Prebiotic actions of galangin, quercetin, and fisetin.
Vascular and anti-oxidant actions of flavonols and flavones.
Clin Exp Pharmacol Physiol. 2004.
Flavonols and flavones are plant-derived polyphenolic compounds that are commonly consumed in the diet. Epidemiological studies indicating that high dietary intake reduces the risk of mortality due to coronary heart disease have provoked interest in the mechanism of this cardioprotective effect. We have investigated the structure-activity relationships of a range of flavonols and flavones with regard to their vascular relaxant and anti-oxidant activity. In rat isolated thoracic aorta, the synthetic flavonol 3',4'-dihydroxyflavonol was found to be a significantly more potent vasorelaxant than the naturally occurring compounds chrysin, apigenin, luteolin, quercetin and fisetin.
Vasorelaxing effects of flavonoids: investigation on the possible
involvement of potassium channels.
Naunyn Schmiedebergs Arch Pharmacol. 2004.
A flavonoid-rich diet has been associated with a lower incidence of cardiovascular diseases, probably because of the antioxidant and vasoactive properties of flavonoids. Indeed, many flavonoids show vasorelaxing properties, due to different and often not yet completely clarified mechanisms of action. Among them, the activation of vascular potassium channels has been indicated as a possible pathway, accounting, at least in part, for the vasodilatory action of some flavonoid derivatives, such as apigenin and dioclein. Therefore, this work aims at evaluating, on in vitro isolated rat aortic rings, the endothelium-independent vasorelaxing effects of a number of flavonoid derivatives, to identify a possible activation of calcium-activated and/or ATP-sensitive potassium channels and to indicate some possible structure-activity relationships. Among the several flavonoids submitted to the pharmacological assay, only baicalein and quercetagetin were almost completely ineffective, while quercetin, hesperidin, quercitrin and rhoifolin exhibited only a partial vasorelaxing effect. On the contrary, acacetin, apigenin, chrysin, hesperetin, luteolin, pinocembrin, 4'-hydroxyflavanone, 5-hydroxyflavone, 5-methoxyflavone, 6-hydroxyflavanone and 7-hydroxyflavone, belonging to the chemical classes of flavones and flavanones, showed full vasorelaxing effects. The vasodilatory activity of hesperetin, luteolin, 5-hydroxyflavone and 7-hydroxyflavone were antagonised by tetraethylammonium chloride, indicating the possible involvement of calcium-activated potassium channels. Moreover, iberiotoxin clearly antagonised the effects of 5-hydroxyflavone, indicating the probable importance of a structural requirement (the hydroxy group in position 5) for a possible interaction with large-conductance, calcium-activated potassium channels.
Short-term administration of dark chocolate is followed by a
significant increase in insulin sensitivity and a decrease in blood
pressure in healthy persons.
Am J Clin Nutr. 2005.
Numerous studies indicate that flavanols may exert significant vascular protection because of their antioxidant properties and increased nitric oxide bioavailability. In turn, nitric oxide bioavailability deeply influences insulin-stimulated glucose uptake and vascular tone. 15 healthy subjects were randomly assigned to receive for 15 d either 100 g dark chocolate bars, which contained approximately 500 mg polyphenols, or 90 g white chocolate bars, which presumably contained no polyphenols. Systolic blood pressure was lower after dark than after white chocolate ingestion and insulin sensitivity was better.
Flavonol antioxidant supplement questions
Does kava kava contain flavonols?
I don't know, if it does the flavonol content is probably not too high.
Do you see
any problems taking
nattokinase supplement, garlic, vitamin C,
serrapeptase enzyme or ahcc
with a flavonol supplement?
As long as the dosages are kept low, it should be okay to take them the same day.