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Vitamin P

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Other Terms:

Bioflavonoids | Polyphenols | Hesperetin | Hesperidin | Quercetin | Quercetrin | Rutin | Phytochemicals


Water soluble, which means that any excess is excreted in urine. The body cannot produce this nutrient, and must get it from the diet regularly.

On this Page: What is Vitamin P · Benefits · Deficiency Signs · Foods · Supplements · RDA · Toxicity | Overdose

What is Vitamin P ?
Vitamin P, more commonly known as bioflavonoids, or flavonoids, are not strictly true vitamins, though they possess vitamin-like properties.

They are a vast array of compounds found in plants, and are classified as plant pigments. These pigments, over 4000 of which have been identified, are responsible for the dazzling colors of fruits and flowers.

Flavonoids belong to the larger group of beneficial plant compounds known as polyphenols.

Heat, acidity, boiling and processing can cause significant loss of flavonoid content in food, as much as 50% or more.  Overcooking of vegetables is especially detrimental.

How Vitamin P Benefits Health
For a start flavonoids are powerful antioxidants that scavenge the harmful free radicals that damage our cells, and that alter genetic DNA, accelerate the aging process, and contribute to development of many diseases.

Free radicals occur naturally in the body as a result of conversion of food to energy, but more is added by toxins such as cigarette smoke, UV rays, radiation, and air and water pollution.  Antioxidants are important as they neutralize these free radicals, and reduce the damage they cause.

Bioflavonoids have been extensively studied, and results show that they provide a number of health benefits.  These can be better understood by looking at different groups of bioflavonoids that include:

  • Citrus Bioflavonoids: these are the flavonoids found in citrus fruit such as oranges, lemons, tangerines, and grapefruit.  They are used and clinically proven in the treatment of hemorrhoids, easy bruising, and varicose veins.  The commonly used citrus bioflavonoids include rutin, quercitrin, naringin, and hesperidin.

  • Quercetin : this is the most abundant and active of the flavonoids, and is a strong antioxidant. It is a major contributor to the medicinal activity of plants.  Research indicates that quercetin has anti-viral, anti-inflammatory, anti-allergic, and powerful anti-cancer properties.

    It is found in commonly eaten food like apples, tea, berries, brassica vegetables, and many nuts, seeds and leaves such as Ginkgo Biloba, St. John's Wort, and Elder.  It is found in especially high amounts in broccoli, red onions, and garlic.  A study has shown that people with a diet rich in red onions and garlic have 20 times less cancer risk.

  • ProanthoCyanidins: more commonly called pycnogenols or OPCs (oligomeric procyanidins) or PCOs (procyanidolic oligomers).

    These are found in many plants, especially pine bark, grape skin, and grape seed.  They are also found in apples, cinnamon, cocoa, barley, bilberry, cranberry, blackcurrant, rhubarb, green tea, and black tea.

    Proanthocyanidins have extremely powerful antioxidant properties. Research shows that they provide 20 times more antioxidant impact than vitamin C, and 50 times more than vitamin E.  They also prolong the lifespan of vitamin C, and boost vitamin E levels in blood vessels.

    Clinical trials of proanthocyanidins reveal many health benefits.  In particular, they offer significant cardiovascular protection.  Grape seed extract, for example, reduces risk of heart disease by reducing inflammation and slowing aggregation of platelets.

    Other uses include antioxidant protection against atherosclerosis, cataracts, diabetes, gastric ulcer and cancer of the large intestines.

    Proanthocyanidin extracts, such as from pine bark and grape seed, have been sold as nutritional supplements for the last 25 years in Europe.  There is no official RDA, but research points to maximum benefits with daily dosages of 60 mg.

  • Green Tea Polyphenols : there are 3 main varieties of teas - black, green, and oolong.  Of the three, green tea, made from unfermented Camellia Sinesis leaves, has the highest concentration of polyphenols that are powerful antioxidants.  Its antioxidant impact can be 20-80 times that of vitamins C and E.

    Green tea polyphenols offer a number of health benefits.  According to research published in the December 1 2004 issue of the American Association for Cancer Research, green tea polyphenols were found to prevent the spread of prostate cancer and to mitigate the risk of other cancers, such as breast, lung and colon cancer.

    Green tea reduces the risk factors associated with heart disease and stroke, by lowering LDL cholesterol and serum triglyceride levels.

    It inhibits oxidation of LDL cholesterol that leads to atherosclerosis. It is also as effective as aspirin in inhibiting platelet aggregation and formation of the abnormal blood clots that cause heart attacks and strokes.  In addition, it increases levels of HDL, or good cholesterol, that helps remove atherosclerotic plaque from artery walls.

    Published studies report that green tea lowers blood pressure and blood sugar levels significantly.  High blood sugar is associated with accelerated aging, cardiovascular disease, diabetes, and body fat.

    Green tea appears to protect the liver against damage from toxins, including alcohol.  Some studies suggest that catechins, one of the polyphenols in green tea, may help treat viral hepatitis.

    Green tea can kill bacteria.  It is known for its deodorising effect and helps kill oral bacteria that cause bad breath and cavities.  It inhibits dangerous intestinal bacteria, but promotes the growth of friendly bacteria.  It may also help treat inflammatory bowel diseases.

    Green tea has traditionally been consumed in China, Japan and India, where its health effects have been known for centuries.  It is known for its detoxifying effect, and ability to burn fat.  It is also used to treat flatulence, promote digestion, and improve heart health.

    It is also a known fact in countries that traditionally consume green tea, that it should not be taken in excess or on an empty stomach. A University of Toronto study published in February 2006 indicates that highly concentrated doses of green tea polyphenols may cause liver damage.

  • Soy Isoflavones : soy contains flavonoids called isoflavones, which are phytoestrogens.  Phytoestrogens ("phyto" = plant) are natural non-steroidal plant compounds that help to balance the effect of estrogen on the body by blocking action of the hormone when levels of it are high, and acting like estrogen when estrogen levels are low, such as in postmenopausal women.

    Evidence from tests and clinical trials indicate that phytoestrogens may help prevent cardiovascular disease, osteoporosis, menopausal symptoms, and prostate and breast cancer. These disorders are less common in cultures with diets rich in soy products and plants.

Flavonoids therefore play an important role in prevention and/or treatment of many health conditions.  Benefits of flavonoids are summarized here.

:: Vitamin P Benefits & Functions
1. most flavonoids are powerful antioxidants that help neutralize harmful free radicals and prevent oxidative stress which damage cells and DNA, and which can lead to aging and degenerative diseases like cancer and Alzheimer's or Parkinson's disease
2. enhances the effects of the other antioxidant vitamins, and increases levels of glutathione, an important and powerful antioxidant
3. enhances the use of vitamin C by improving its absorption, prolonging its effectiveness, and protecting it from oxidation
4. works with vitamin C to strengthen and protect blood vessel structure, and reduce prolonged bleeding, bruising, and nosebleeds
5. clinically proven in treatment of hemorrhoids and varicose veins
6. works with vitamin C to alleviate oral herpes
7. flavonoids with vitamin C may help prevent cold sores; to treat cold sores, try taking 1000mg of vitamin C with 1000 mg of bioflavonoids, then reduce to 500 mg of each 3 times a day
8. may help prevent and treat cataracts
9. stimulates bile production
10. used in treating sports injuries as it relieves pain, bumps, bruises
11. helpful for relieving leg and back pains
12. has antibiotic-like effect due to anti-viral and anti-bacterial activity, and also anti-allergic and anti-inflammatory properties
13. protects against cancer by inhibiting tumour growth
14. reduces risk of cardiovascular disease and heart attack by lowering LDL cholesterol level and stopping blood platelets from clumping, which minimises blood clotting and prevents build-up of atherosclerotic plaque on artery walls as effectively as aspirin, but without its side effects
15. known to lower hypertension (high blood pressure) and so lessen risk of stroke and heart disease
16. quercetin has natural anti-histamine and anti-inflammatory properties, and taken with bromelin may be useful in preventing and treating asthma and other allergies


Vitamin P Deficiency Symptoms and Causes
Deficiency is not common, but on the other hand many people do not take enough bioflavonoids for optimal health.

The most likely contributing factor is a diet that is low in vegetables and fruits, or that is skewed towards highly processed vegetables and fruits. Processing can cause significant loss of bioflavonoid content in food.  For instance, juice that does not contain the pulpy fibrous part of the fruit, or natural colors of vegetables that are lost in canning and reheating.

Stress, diuretics, drugs such as oral contraceptives, anti-inflammatories, oestrogens, and aspirin, also increase intake requirements for flavonoids.

:: Vitamin P Deficiency Symptoms
1. easy bruising
2. excessive swelling after injury, such as sports injuries
3. frequent nose bleeds
4. hemorrhoids or varicose veins
5. weak immune system, resulting in frequent colds or infections


Vitamin P Foods
Almost all vegetables, fruits, spices and herbs contain bioflavonoids, as do some grains and dried beans. There is a vast range of types of flavonoids, with different ones from different foods.

Green tea for example, contains flavonoids called catechins that can reach up to 100 milligrams per cup. Berries, especially black raspberries, have the highest concentrations of the flavonoids anthocyanins.

The foods listed below can each contain several types of flavonoids.

Rich bioflavonoids foods · white material just beneath the peel of citrus fruits · celery · garlic · red onions · broccoli.

Other good bioflavonoids sources · buckwheat · dry beans such as red beans, black beans, pinto beans · fruits such as blueberries, strawberries, raspberries, apples, apricots, blackcurrants, cherries, grapefruit, grapes, guavas, lemons, oranges, papaya, pears, prunes · herbs such as bilberry, hawthorn, ginkgo, licorice, pine bark, rose hips, yarrow and milk thistle · green tea · red wine · parsley · peppers · romaine lettuce · tomatoes · brassica (or crucifer) vegetables such as Brussel sprouts, cabbage, cauliflower, collard greens, cress, kale, kohlrabi, mustard greens, pak choi, swedes, turnips.


Vitamin P Supplements
Taking vitamins and minerals in their correct balance is vital to the proper functioning of all vitamins.  They work synergistically, which means that the effectiveness of any one nutrient requires or is enhanced, sometimes dramatically, by the presence of certain other nutrients.

For this reason, if you are looking to take supplements for maintenance of optimal health, the recommended approach is to take a multi-vitamin that has the proper balance of all the necessary nutrients your body needs.

For a list of reputable top ranked vitamin and mineral supplements chosen in an independent supplement review, see Best Multivitamin Supplements. Many of these are manufactured to pharmaceutical or nutraceutical GMP compliance, which is the highest multivitamin standard possible.

Keep in mind, however, that while vitamin supplements are useful to plug nutritional gaps that are almost inevitable in modern diets, and to ensure we get optimal doses of nutrients, they are no substitute for a good diet. Instead, use them to complement a healthy diet and lifestyle.


Vitamin P RDA (Recommended Dietary Allowance)
There are no official dosages for bioflavonoids. Doses in most supplements sold range from 30 to 200 milligrams a day which is acceptable for general maintenance.

Clinical trials tend to be based on much higher doses of between 500 to 2000 mg (milligrams). For therapeutic purposes the range can be between 50 to 500 mg per day.


Vitamin P Overdose Symptoms, Toxicity Level & Side Effects
With the exception of green tea, research on flavonoids in general shows no known toxic effects.  High doses do not appear to cause serious side effects, even for amounts as high as 100 grams a day.  Excess intake is simply excreted in urine.

The main symptom of flavonoid overdose is diarrhea.

As for green tea, highly concentrated doses of it might contain too much caffeine for cancer and hepatitis patients, and for those people sensitive to caffeine.

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1. U.S. National Libary of Medicine [NLM] & National Institutes of Health [NIH]: MedlinePlus. NLM-NIH home page. <http://www.nlm.nih.gov/medlineplus>. Use the built-in search function to find specific data. Accessed 2009 March – June.

2. Oregon State University, Linus Pauling Institute. Department of Environmental and Molecular Toxicology: Antioxidant activities of flavonoids. <http://lpi.oregonstate.edu/f-w00/flavonoid.html>. Accessed 2009 Jul 05.

3. The George Mateljan Foundation: The world's healthiest foods [WHFoods]. WHFoods home page. <http://www.whfoods.com>. Accessed 2009 March – June.

4. Balch JF, Balch PA. Prescription for nutritional healing: A practical A-Z reference to drug-free remedies using vitamins, minerals, herbs & food supplements. Garden City Park, New York: Avery Publishing; 1990.

5. Hooper L, Kroon PA, Rimm EB, Cohn JS, Harvey I, Le Cornu KA, Ryder JJ, Hall WL, Cassidy A. Flavonoids, flavonoid-rich foods and cardiovascular risk: a meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition, 2008;88 38-50.

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