Proanthocyanidins

By G. Douglas Andersen, DC, DACBSP, CCN

Two years ago I began to receive enthusiastic letters, cassette tapes, testimonials, and a lot of claims about a new wonder nutrient called pycnogenol. I had doctors contact me to sell it; others urged me to write about it.

Pycnogenol is a trademark name for a type of bioflavonoid found in the bark of the French maritime pine tree. What got my attention was the claim that this bioflavonoid had 50 times the antioxidant capabilities of vitamin E and 20 times the antioxidant capabilities of vitamin C. My attention was somewhat dampened because the only source of this nutrient seemed to be through multilevel marketing companies. I passed on the product and declined to write about it.

As sales of pycnogenol skyrocketed in the United States, nutrition companies began to read the research on this European product. They found that pycnogenol was in a family of bioflavonols called proanthocyanidins, which are the precursors of red, blue, and violet pigments in plants. It turns out that in addition to pine bark, these proanthocyanidins can be found in grape skins, grape seeds, cranberries, blueberries, blackberries, red wine, red cabbage, red apple skins, strawberries, and black cherries. As people continued to dig, they found that most of the research done on proanthocyanidins was not performed on the extract of pine bark but on the extracts from grape skin and grape seeds. The scientist who first isolated this flavanol from pine bark named it pycnogenol in the 1970s. A few years later when researchers learned that pycnogenol was actually a proanthocyanidin, the name pycnogenol was patented for the extraction process from pine bark and trademarked for marketing purposes. Part of the initial marketing in the United States centered on the fact that pycnogenol only comes from the bark of the French maritime pine tree, and that if you don't have pine bark extract you will not have a product with the unique function of pycnogenol. However, since proanthocyanidin is the bioactive molecule, many people feel it doesn't matter what source it comes from. Interestingly enough, grape extract has an 8-10 percent higher content of proanthocyanidin than the French maritime pine tree. It is also much less expensive to obtain proanthocyanidin from grape skins and seeds, and this grape extract contains a powerful antioxidant called B2-3'-0-gallate not present in pine bark. It is also interesting that in Europe grape-based proanthocyanidins outsell their pine tree-based competitors by a healthy margin.

What Do Proanthocyanidins Do?

Proanthocyanidins are first and foremost a powerful multifunction antioxidant. While many antioxidants are able to inactivate a single pro-oxidant, proanthocyanidins have direct antioxidant capabilities against (1) superoxide anion; (2) hydroxyl radicals; and (3) lipid peroxide. Proanthocyanidin also have indirect antioxidant capabilities. They can bind with and neutralize iron (a powerful pro-oxidant). They can also reduce the production of xanthine oxidase, another pro-oxidant and precursor of hydrogen peroxide. Finally, they have indirect antioxidant effects by directly helping vitamin C. This is accomplished by neutralizing ascorbic oxidase (an enzyme that breaks down vitamin C) and reducing glutathione, which assists in the conversion of dehydroascorbate (oxidized vitamin C) to ascorbate (active vitamin C).

Proanthocyanidins also are anti-inflammatory molecules. They reduce the formation of various leukotrienes and two series prostaglandins. They also have antihistamine effects by blocking mast cell degranulation (degranulated mast cells release histamine). Finally, proanthocyanidins have a strong effect on the vascular system, specifically capillaries. They stick or bind with collagen fibers to support capillaries and collagen in the ground substance around capillary cells. Their presence in the collagen not only strengthens and reinforces it, but serves as a ready source of antioxidants which collagen can use to combat free radical attacks. Proanthocyanidins also indirectly support the vascular system by, as previously explained, its sparing effects on vitamin C, which is a key nutrient in collagen synthesis.

Research from Europe has demonstrated that proanthocyanidins can be used as nutritional support for the following conditions: 

1. capillary fragility (easy bruising);
2. diabetic vascular disease;
3. varicose veins;
4. eye problems including macular degeneration, hypersensitivity to light, and poor night vision;
5. allergic reactions such as hay fever;
6. general internal and external inflammatory conditions from colitis to arthritis.

Dosing

Proanthocyanidins are easily and rapidly absorbed orally. Because they are water soluble, they should be taken daily. Dose recommendations tend to vary. Mine are as follows: 30-50 mg per day for prophylactic use as a general antioxidant, either individually or contained in a multiple vitamin product. Therapeutic doses can range from 100-500 mg a day depending on the nature and extent of the problem, the size of the patient, and the integrity of the gastrointestinal tract. Translation: a large person with arthritis, easy bruising, and a long history of non-steroidal anti-inflammatory use would require more aggressive doses. A patient such as this should try proanthocyanidins for at least a four week period. If they report significant subjective improvement, consumption of proanthocyanidins should be continued. The dose should be gradually tapered to a minimum level necessary to maintain the patient's satisfaction. For acute inflammation, such as a sprained ankle or back, two to seven days of 300-500 mg in divided doses is appropriate. For antihistamine uses, such as a flare-up of allergies, 300 mg as soon as symptoms commence will many times result in symptom suppression in 15 to 45 minutes. In cases where one dose is not enough, and symptoms continue, dosing may continue at a level of 100 mg per hour until symptoms subside.

Safety

Proanthocyanidins are exceedingly safe. The only problems that are rarely seen would include occasional loose stools with higher doses and intolerance by a few chemically hypersensitive individuals. For stool problems, simply lower the dose. Chemically hypersensitive and intolerant individuals will generally have a host of problems and can be quite difficult to manage. A second opinion with an environmental medical specialist should be considered.