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Proanthocyanidins are a group of bioflavonoids which are extracted from pine bark and grape seeds, which also potentiate vitamin C. It is a classic example of a plant-medicine or vitamin (“phytamin”).

Professor Jacques Masquelier of Bordeaux discovered the biochemistry and isolated the first compound in 1951. At first, he believed there was only one compound: leucocyanidin. He coined the word Pycnogenol (1979) to describe an entire class of bioflavonoids.

Proanthocyanidins are composed of polyphenols, or Oligomeric Proanthocyanidin Complexes (OPC’s) which are defined by the exclusive property of producing a red pigment (anthocyanidin) hence the efficacy of red grapes and red wine.. There are, in fact, several procyanidins: oligomeric and monomeric. About 85% of the compounds of proanthocyanidins have been identified as procyanidins. Of these, about 60% are oligomeric procyanidins (OPC’s): dimers, trimers and tetramers of catechin and epicatechin; 20% are oligomers and phenolic acids such as gallic acid.

These may, simply, be regarded as esters of bioflavonols. On a more mundane level, another close relative, with a long history of consumption, especially in Japan, is green tea.

Bioflavonoids and carotenoids provide the variation of colors in the vegetable kingdom. Chlorophyll provides the green which is the central component of a plant’s energy system but bioflavonoids contribute: blues, purples, emerald green and some reds; carotenoids provide the yellow-orange-red hues (like carrots). They are concentrated in the skins and seeds. Flavonoids function to screen plants from light.

Method of Action

A recent book by chiropractic physician, James D. Krystosik states that proanthocyanidins are effective against 60 diseases and proceeds to list about half of them. The major author in this field, Richard A. Passwater, Ph.D. refers to 80 diseases (70 of them radical related) and lists about a quarter of them.

The inference is clear, there are certain main benefits of proanthocyanidins which translate to particular disease categories and if one wanted to, one could expand upon each heading with numerous sub-divisions. Thus, while proanthocyanidins are well known for their beneficial effect on the heart one must not ignore the attendant vascular system, which includes a second major organ the lungs but also encompasses the skeleton and spleen where some blood cells originate; furthermore, oxygenated blood reaches, quite literally, every cell in the body, so that every system, indeed every class of cells, may also be itemized, in some way, dependent upon an adequate supply of nutrients, specifically, proanthocyanidins™. Every disease associated with any of these components could, then, be justifiably enumerated.

Some convenient categories are:-

· Immune System Enhancer
· Free radical scavenger
· Anti-inflammatory
· Anti-histamine

Therapeutic Approaches

Individuals who may wish to take a hard look at the potential benefits of supplementing with proanthocyanidins include:

· middle-aged, older segments of the population;

· those who do not eat sufficient fruits and vegetables;

· those with “Western” diseases: obesity, diabetes and osteoporosis;

· patients with other degenerative diseases e.g. arthritis;

· families with a high incidence of cancer;

· drug addicts (both prescription e.g. antibiotics, anti-inflammatories) and recreational (including alcohol and cigarettes);

· individuals in extreme lifestyles, less likely to be explorers crossing the ocean but those who train for fitness in an intense manner, on a daily basis, throughout the year;

· anyone with a compromised immune system, vulnerable to infections e.g. asthmatics, yeast infections (“candida”);

· combinations of the above e.g. female members of families with a history of breast cancer; men whose relatives have had prostate problems with advancing age (i.e. almost everyone!).

The noted medical nutritionist, Lendon Smith, M.D. has commented that he has always, innately, eaten apples and grapes, whole, including the skin and even chewing up the seeds. At one point he rationalized that he must be getting something akin to vitamin A. Now, he ponders that his taste buds may have led him to boost his consumption of proanthocyanidins

Supplementation - General Guidelines:

James D. Krystosik, D.C. conveniently summarized many of Professor Masquelier’s suggested dosages from his book: “OPC in Practice”.

The typical standard, or maintenance, dosage that Professor Masquelier recommends is: 1.5 mg per 3 pounds of body weight for adults and half that for children on a daily basis.

In the event of an infection the adult dose increases to 1.5 mg per 1 pound of body weight i.e. three-fold the regular dose.

Toxicity Factors

Proanthocyanidins, are composed of bioflavonoids, the best-known of which are quercitin and rutin.

The controversial Ames Test has caused quercitin to be labeled “mutagenic” but the validity is disputed, together with similar results for vitamin C itself and rutin.

Rutin, like other bioflavonoids, has a low toxicity and is generally recognized as safe.

Otherwise there have been no reports expressing concern about the use of proanthocyanidins such as pine bark, grape seeds, red grapes, red wine and green tea etc.



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