Vitamin supplements guide   Vitamins & health supplements guide

 
Bioflavonoids (vitamin P) review
Basics: a class of water-soluble plant pigments with antioxidant, anti-inflammatory, antiallergenic, antiviral, and anti-carcinogenic properties.
Benefits: helps protect this vitamin C against oxidation, stimulates bile production, lowers cholesterol levels, treats and prevent cataracts, involved in maintaining the health of the collagen.
Dosage: 500 mg per day is indicated for supplementation.
Sources: citrus fruits, red wine, green tea, onions, grapefruit seeds, apples, ginkgo biloba, hawthorn and Chinese scullcap.
Overdose: bioflavonoids are generally safe, high doses may cause diarrhea.
 
Editor's choice: Citrus Bioflavonoid
Citrus bioflavonoids work synergistically with Vitamin C. They each enhance the action of the other. Citrus bioflavonoids are needed for Vitamin C to be used effectively by the body. They also lengthen the effectiveness of Vitamin C by slowing down its breakdown. Citrus bioflavonoids help relieve allergies, fight viruses and the common cold, and support the reduction of inflammation. Click here for more information.
 

Quercetin


Quercetin is a yellow powdered crystalline compound, synthesized or occurring as a glycoside in the rind and bark of numerous plants. Quercetin is considered a phytoestrogen. Phytoestrogen is a plant substance with similar functions as that of estrogen. Quercetin is a member of the class of flavonoids called flavonols. It is widely distributed in the plant kingdom in rinds and barks. In the body, quercetin has potent antioxidant and anti-inflammatory activity, where it can protect cellular structures and blood vessels from the damaging effects of free radicals.
 

Quercetin functions, uses, and health benefits


Quercetin is effective in the treatment and prevention of many disorders, from asthma to cancer to heart disease.
Quercetin have antioxidant, anti-inflammatory, antivral, immunomodulatory, anticancer and gastroprotective activities. Quercetin blocks an enzyme that leads to accumulation of sorbitol, which has been linked to nerve, eye, and kidney damage in those with diabetes.

Quercetin possesses potent antioxidant properties. It protects LDL cholesterol from becoming damaged. Quercetin prevents damage to blood vessels by certain forms of cholesterol and other chemicals produced by the body. LDL cholesterol is an underlying cause of heart disease. Quercetin also works as an antioxidant by scavenging damaging particles in the body known as free radicals. People with diabetes are at higher risk of blood vessel damage from free radicals. Quercetin may reduce the risks of certain cancers developing.

Quercetin acts as an antihistamine and has anti-inflammatory properties. Quercetin inhibits some inflammatory enzymes, such as lipid peroxidases, and decreases leukotriene formation. Quercetin opposes the actions of the histamines in the body. Histamines are responsible for allergic and inflammatory reactions. It can help reduce the inflammation that results from hay fever, allergies, bursitis, gout, arthritis, and asthma. It may lessen other asthma symptoms.

 

Quercetin dosage, intake, recommended daily allowance (RDA)


There is no standard dietary recommendation for quercetin intake. General supplementation for adults is 100 to 250 mg three times per day. Quercetin supplements are often packaged with bromelain (an enzyme found in pineapple) as an anti-inflammatory agent.
 

Sources of quercetin


Sources of quercetin include onions, apples, green tea, and black tea. Smaller amounts are found in leafy green vegetables and beans.