Recognizing High-Quality OPC: Features and Quality Criteria

OPC: Secondary Plant Compounds and the French Paradox

The acronym OPC stands for oligomeric proanthocyanidins, which belong to the group of secondary plant compounds. Shortly after their discovery by Jacques Masquelier in 1948, it became clear that they occur in varying concentrations in many plants and are produced by them, for example, as pigments, defense compounds against herbivores, as well as fragrance and flavor compounds.

High OPC concentrations are especially found in the skins and seeds of grapes. This characteristic is considered responsible for the so-called “French Paradox,” which suggests that despite consuming more red wine, the French suffer less from cardiovascular diseases. However, regular alcohol consumption cannot be equated with a healthy lifestyle in the long term. A high-quality supplement is a useful alternative to help you benefit from the advantages of OPC without the risks.

OPC and its Properties

Proanthocyanidins are assigned to the flavanol group due to their structure. They consist of several linked catechin molecules. Depending on the number of linked catechins, we distinguish between monomeric proanthocyanidins, oligomeric proanthocyanidins (OPC), and polymeric proanthocyanidins. From the combination of two catechin molecules, we speak of OPC, though it remains scientifically debated where exactly polymer chains begin.

It is undisputed that OPC ingested from food is partly absorbed in the intestine and partly metabolized by intestinal microorganisms.

Grape Seed Extract Is Not the Same as OPC: How to Recognize High-Quality Ingredients

Currently, there is no unified definition for OPC. In 2000, a group of U.S. researchers first defined OPC as proanthocyanidins with a chain length of two to ten catechin molecules1. An expert panel that established guidelines for the analysis and labeling of grape seed extracts in 2001 did not provide a precise definition for OPC2. Therefore, there is significant variation in the quality of OPC products offered on the market.

While some mislabeling may be due to ignorance, unfortunately, there are also manufacturers who deliberately attempt to upgrade lower-quality raw materials by adding cheap peanut polyphenols, for instance, to display a higher total polyphenol content. In such cases, not only is the actual OPC content often significantly lower than advertised, but these products are also frequently offered without accompanying documentation, leaving you as the customer with no certainty about what substance is actually in the capsules.

But what does that mean for you? As a manufacturer, it's routine for us to send raw material samples to the lab for analysis, determine the actual OPC content, evaluate and compare the results, and ultimately choose a raw material based on its quality. For you, this effort is disproportionately high if you’re simply trying to find the right product. That’s why we’ve created a simple checklist to help you identify a high-quality OPC product.

Quality, Raw Materials, Processing: What to Look For When Buying OPC

First, check the ingredient list:

• How is the raw material declared?

  An OPC-rich grape seed extract is not comparable to grape seed meal or grape meal, whose OPC content is only about 1-2%. Therefore, "Grape Seed Extract" should be listed first in the ingredients.

• How is the OPC content listed?
The amount of grape seed extract does not correspond to the amount of OPC it contains. The statement "95% polyphenols = 95% OPC" is particularly misleading. The percentage only represents the total polyphenol content and has nothing to do with actual OPC levels, which theoretically could be less than 1%. Realistic OPC levels range between 40-50%.

• What other ingredients are included?
A high-quality grape seed extract can be processed without the use of additional agents such as silicon dioxide, magnesium stearate, or talc. The more natural the product, the fewer unnecessary additives should be listed.

Once you’ve checked these points, the next question is about the general quality of the raw material.

• Is there an analysis certificate for the grape seed extract?
The grape seed extract should be tested for possible contamination by heavy metals, microorganisms, and pesticides before processing. The results, along with the polyphenol and OPC content, should be provided in an analysis certificate. This should be available for the current batch and included with your order.

Reliable Quality Controls for High-Quality OPC Products

An analysis certificate for grape seed extract should indicate the content of polyphenols and actual OPC. High-quality products consist of 95-100% polyphenols, with an OPC content of 40-50%. If the OPC value is significantly higher, either incorrect labeling occurred, or chemical solvents were used to increase the OPC yield. In the U.S., extraction agents are allowed that are not approved for food production in Europe. An OPC content of 50% is realistic and sufficient for producing a highly concentrated product. Importantly, the value should be determined before processing. If the final product contains other plant extracts, this could distort the OPC content result.

In addition to these OPC-specific analyses, a possible contamination by heavy metals, microorganisms, and pesticides is also checked to ensure the product is safe for daily consumption.

To give you an idea of such an analysis, we have linked our certificate for OPC240 here, where you can find all the relevant points we have explained up to this point.

We Guarantee the Outstanding Quality of Our OPC Through Analysis Certificates

Our OPC products are high-quality supplements with certified quality. For both OPC120® plus Acerola and OPC240 plus Acerola and OPCpur, the quality has been confirmed by independent laboratories. You can view the corresponding certificates on our website.

Our Commitment to Your Well-Being: High-Quality OPC Capsules from BioProphyl

We have been offering OPC for more than 25 years, and our products feature the following characteristics:

• Grape seed extract from French grapes with 50% OPC
• Manufactured exclusively in France and Germany
• No additives or fillers
• Various dosages for different needs
• Analysis of each batch available online before purchase

You can choose the product that best suits your individual needs from our range of OPC120®, OPC240, and OPCpur.

Would you like to combine OPC with natural vitamin C? We recommend OPC120® with 120 mg of OPC and 12 mg of natural vitamin C as a starting point. One capsule a day equips you for everyday challenges. If you want more, you can take two OPC120® capsules, or opt for OPC240, which provides 240 mg of OPC and 34 mg of natural vitamin C per capsule.

With our OPCpur, you receive pure OPC without any other ingredients. The capsules contain 120 mg of pure OPC, and nothing else. They are free from fructose and can therefore also be consumed if you have a fructose intolerance.

If you're unsure about which product to choose, just give us a call. We're happy to advise you and help you find the product that best suits your needs.