Bioflavonoids (bioavailable flavonoids, vitamin P) are a class of water-soluble plant pigments with antioxidant, anti-inflammatory, antiallergenic, antiviral, and anti-carcinogenic properties. This is the collective name given to rutin, hesperidin and quercetin and a range of other naturally occurring compounds including the oligomeric pro-cyanidins found in red wine. Strictly speaking, bioflavonoids are not true vitamins, though they are sometimes referred to as vitamin P. They are essential for the absorption of vitamin C, and the two should be taken together. Bioflavonoids are extremely necessary for the absorption of vitamin C, and bioflavonoids should be taken together. The human body does not produce bioflavonoids, they must be supplied through diet.

Bioflavonoids have antioxidant, anti-inflammatory, antiallergenic, antiviral, and anti-carcinogenic properties. Like vitamin A, vitamin C and vitamin E, bioflavonoids are antioxidants. Antioxidants can rid the body of free radicals, toxic byproducts of chemical reactions that take place in the body every day. The body is exposed to free radicals through exercise, pollution, smoking, and many other factors. Bioflavonoids are often used in vitamin C formulas because they enhance the absorption and action of this vitamin. Bioflavonoids help maximize the benefits of vitamin C by inhibiting its breakdown in the body.
Some of the most well known flavonoids, for example, include:

arw most potent PCOs are those bound to other PCOs
arw exist in many plants and red wine
arw commercially available sources are from grape seeds and bark from the maritime pine
arw serves as backbone for other flavonoids such as citrus flavonoids: rutin, quercitrin, hesperidin
arw these derivatives have sugar molecules attached to the backbone
arw most active of the flavonoids
Citrus bioflavonoids
arw include rutin, quercitrin, hesperidin, naringin
arw standardized mixture of rutinosides known as hydroxyethylrutosides (HER)
arw clinical results have been obtained in treatment of capillary permeability, easy bruising, hemorrhoids, and varicose veins
Green Tea Polyphenols
arw derived from tea plant camellia sinensis
arw produced by steaming the fresh cut leaf
arw polyphenol indicates presence of phenolic ring in the chemical structure
arw polyphenols = flavonoids
arw polyphenols in green tea: catechin, epicatechin, epicatechin gallate, epigallocatechin gallate, and proanthocyanidins
arw epigallocatechin gallate = most significant active compound

What is Bioflavonoids?
Bioflavonoids are a group of naturally occurring plant compounds, which act primarily as plant pigments and antioxidants. They exhibit a host of biological activities, most notably for their powerful antioxidant properties. Bioflavonoids work with other antioxidants to offer a system of protection. Numerous studies have shown their unique role in protecting vitamin C from oxidation in the body, thereby allowing the body to reap more benefits from vitamin C.

Bioflavonoids are present in all botanical supplement products and foods. In fact, many medicinal herbs owe their curative actions to the bioflavonoids they contain. Besides the important antioxidant effects, bioflavonoids help the body maintain health and function in many ways. They have been shown to be anti-mutagenic, anti-carcinogenic, anti-aging, and promote structure and function in the circulatory system.

Where it is found
Bioflavonoids are abundant in the pulp and rinds of citrus fruits and other foods containing vitamin C, including red wine, green tea, onions, grapefruit seeds, apples, and other fruits and berries. Many medicinal plants contain bioflavonoids such as ginkgo biloba, hawthorn and Chinese scullcap. Citrus flavonoids are found in citrus fruits, rutin in buckwheat, epigallocatechin gallate (EGCG) in green tea, anthocyanidins in bilberry, and naringenin in grapefruit. Oligomeric proanthocyanidins, are found in grape seeds and skins. Quercetin is found in onions, tea, and apples.

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Bioflavonoid Complex
Bioflavonoids and Cardiovascular Health
Bioflavonoids And Therapeutic Potential

Benefits / uses
The main health benefits of bioflavonoids fall into two categories: health-promoting effects and therapeutic effects. The health-promoting effects include better eyesight, improved cardiovascular health, increased capillary strength, improved structure of connective tissues and appearance of skin, and a stronger immune system. Bioflavonoids also offer the health-promoting effect of lowering the risk of some diseases, such as atherosclerosis, cancer, arthritis, and gastrointestinal disorders. The therapeutic applications include treating a variety of diseases and disorders. Several of these are coronary heart disease, allergies, inflammation, hemorrhoids, respiratory diseases, viral infections, some types of cancer, and peptic ulcers.


arw increase intracellular Vitamin C levels
arw decrease capillary permeability and fragility
arw scavenge oxidants and free radicals
arw inhibit destruction of collagen
arw crosslinks collagen fibers to reinforce the natural crosslinking
arw prevents free radical damage
arw inhibits enzymatic cleavage of collagen by enzymes secreted by leukocytes in inflammation and microbes in infections
arw prevents release and synthesis and compounds that promote inflammation and allergies (histamines, prostaglandins, leukotrienes)
arw antioxidant effects are beneficial in:
  arw aging process
  arw chronic degenerative diseases (heart disease, arthritis, and cancer)
  arw fat and cholesterol oxidation
arw antioxidants are produced by:
  arw inhibiting xanthine oxidase noncompetitively(oxygen free radicals)
arw on the cellular level: PCOs are incorporated into the cell membranes along with the antioxidant effects offer great protection to cells against free radical damage.
arw anti-inflammatory activity due to inhibition of initial processes of inflammation
arw inhibits manufacture and release of histamine
arw potent antioxidant activity and Vitamin C sparing action
arw beneficial effects for diabetics
arw helps prevent diabetic cataracts, and retinopathy
  enhances insulin secretion
arw protects pancreatic beta cells from free radical damage
arw antiviral activity
arw activity vs. herpes virus type 1, parainfluenzae3, polio virus type 1, and respiratory syncytial virus
arw in vivo, inhibits viral infection
arw may be of some benefit in the common cold
Citrus Bioflavonoids
arw antioxidant effects
arw increase intracellular Vitamin C, rutin, hesperidin, and HER
arw beneficial effects on capillary permeability and blood flow like PCOs
arw anti-allergy and anti-inflammatory effects like quercetin
Green Tea Polyphenols
arw Potent antioxidant effects
arw Increase activity of antioxidant enzymes in the small intestines, liver, lungs, and small bowel
arw Inhibit formation of cancer causing compounds like nitrosamines in vitro
arw Suppressing activation of carcinogens
arw Trapping cancer causing agents
arw Forms of cancer that green tea prevents best:
  arw Cancers of GI tract (stomach, small intestine, pancreas, colon)
  arw Cancer of the lungs
  arw Estrogen related cancers (inhibits estrogen interaction with its receptor)
arw Consumption of green tea with meals inhibits formation of nitrosamines (nitrites combined with amino acids)
No dosage has been determined but 500 mg per day is indicated for supplementation, typically recommended dosage for women in menopause is 1000 - 1500 milligrams a day.

Possible Side effects / Precautions / Possible Interactions:
Bioflavonoids are generally safe. Excesses will be stored to a limited extent in the body, though most of the excess will be eliminated in the urine and sweat. No consistent toxicity has been linked to the bioflavonoids. However, extremely high doses may cause diarrhea, pregnant women are advised not to take megadoses of bioflavonoids.

Research studies / References
Flavonoids (isoflavonoids and neoflavonoids)., IUPAC Compendium of Chemical Terminology

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American Cancer Society, Quercetin

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Phenolics:figure 4

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