Questions & Answers for OPC-1-2-3 products
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We try our best to compile all questions on our isotonic OPC antioxidants received from our customers or potential customers.

1. How to take this isotonic OPC supplement? May I take 2 doses a day?

For adults of 18 and older, pour 3/4 of a teaspoon of isotonic OPC powder (3.33 g) into a glass or a cup. Add 60 mL (2 ounces) of room temperature water and stir well. Drink it on empty stomach in morning, or at least 2 hours after a meal during the day. Take once daily or more as directed by your physician. Keep the bottle closed tightly from moisture. You may have a meal 5-10 minutes later.

We recommend 90-300 mg of total OPC a day. For general health maintenance, 90-150 mg of total OPC extract is adequate, while you may take 2 doses (180 mg or 300 mg) a day for a short period of time (2-3 weeks). A total of 150-300 mg of OPC extract is needed for people of particular medical conditions, such as hypertension, diabetes, muscle cramp, chronic venous insufficiency, platelet function. Consult your health care professional if you have any specific questions.

We supply a free powder-measuring scoop with each bottle of the products. The powder-measuring scoop is 3/4 teaspoon in volume, each serving is a full scoop. You may take slight more as your choice.

2. Does OPC affect the mineral absorption in the human body as polymeric proanthocyanidins do?

OPCs are generally safe at the recommended dosages, as shown by extensive human clinical studies. No mineral absorption was affected using our high quality OPC ingredients in the clinical studies. For precaution, people of anemia should not take OPC supplement such as pine bark extract, grape seed extract, and/or red wine extract.

The isotonic OPC formula is especially safe, as compared with OPC capsules and tablets. As directed, isotonic OPC should be taken with empty stomach to allow fast and efficient absorption without interference with absorption of other food nutrients. Isotonic OPC should be taken separately during the day if one also takes any mineral supplement such as calcium, at least 2-3 hours apart.

OPC and polymeric proanthocyanidins are both metal chelators. But not all the metal chelators interfere with mineral absorption. Polymeric proanthocyanidins are different from OPC, have been demonstrated to be un-absorbable, and therefore, interfere with mineral absorption by"walking away" with mineral nutrients.

3. I tried your OPC product. It tastes good, not that astringent as I think. But I don't believe it is the best isotonic OPC. I just searched Google and Ebay, one of other isotonic OPC products is sold at $69.95, at least another 3 similar isotonic OPC products are sold at $39.95, $40.00 and $45 for the same sized package (OPC/300g). One of your OPC products I bought is sold at $38.8. There is some reason for the differences.

Our FrenchGlory ® isotonic OPC-90 antioxidants are on sale now for $38.80. The price could go up any time to $48.8. I would say that you cannot judge the best isotonic OPC product (the same 300 g bottle) based on the prices. We give reasons in several web pages on this site (e.g. Our OPC ingedients) to claim the world-best isotonic OPC. I hope you can read more about our raw OPC ingredients we use, which are the best OPC ingredients we could find. Our low price is just another reason for claim of the best OPC product. Other sellers make more by selling the similar isotonic OPC 300g bottles with lower quality of OPC ingredients. We want to sell the better isotonic OPC for 3-months supply at lower prices and make less, passing all the savings to OPC consumers.

As you said by phone, you used to take grape seed extract capsules. This is your first time to try isotonic OPCs. The multi-level marketing isotonic OPC product at $69.95 is very expensive, and contains less OPC extracts (75 mg) than FrenchGlory OPC (90 mg). Even though the multi-level marketing isotonic OPC - 300g has a big brand name pine bark extract as a token for decoration, they keep the secrets about their OPC grape seed extract and OPC red wine extract. The other 3 isotonic OPC products at $39.95, $40 and $45 all use unclear OPC sources of pine bark extract, grape seed extract, and red wine extract, the 3 key OPC ingredients. You made a right choice of FrenchGlory OPC-90. As we don't hide any secret of the OPC ingredients, you know what you swallow. Our suggestion to all OPC consumers is that don't buy an OPC product unless you can find the OPC ingredient makers and specifications on their sellers' web sites.

4. May diabetic patients take isotonic OPC products that contain sugars?

Yes. Many scientific studies indicate that OPC have considerable nutritional benefits for diabetes and related complications, as discussed in several places through this web site. Our isotonic OPC antioxidant formula contains sugars, but only about 1% of the average daily value of the needed amount. This amount does not cause any burden to diabetic patients.

5. Are the OPC ingredient specifications on the OPC manufacturers' web sites reliable?

It depends. According to our PhD scientists, the best OPC ingredients as grape seed extract and pine bark extract in the commercial market contain OPC in about 70-80%. Many sellers label their products as OPC 85%, OPC 90%, OPC 95%, etc. Those OPC sellers are not credible. One reason for this confusion is that some OPC sellers or OPC ingredient manufacturers have no idea what "OPC" really means. They add the monomers and polymeric proanthocyanidins into their OPC content. Some other OPC sellers just want to make the numbers more attractive to unknowledgeable OPC consumers.

Our OPC ingredient manufacturers are credible companies, and our OPC ingredients have very detailed specifications for OPC consumers to evaluate. In principle, OPC ingredient manufacturers are legally reliable for their OPC specifications posted on their web sites, if the OPC manufacturers are GMP-certified in countries of strict government regulations, such as those in North America and many in Europe. An OPC ingredient manufacturer has too many risks to tolerate if they make false statements about the specifications, which can be easily audited by a third party or government.

But the reality is that some OPC products may not contain the amount of the OPC or any OPC at all that is written on the label, and some products in the name of OPC may include other substances (contaminants, such as much polymeric proanthocyanidins). One of the tricks some OPC sellers play is to give little information about their OPC specifications in writing in order to avoid their legal liabilities. Another myth for OPC ingredients is that manufacturers play the ambiguity. For example, some OPC ingredients labeled as Proanthocyanidins > 95%. You have no way to understand what they mean. They probably mean Polyphenols > 95%. But in the other cases, an OPC ingredient is labeled as"Proanthocyanidins > 80% and Polyphenols > 30%." It is very confusing.

Natural Product Association of USA has much stricter rules for its members. Our final OPC consumer products are blended and packed in a nutraceutical company certified by Natural Product Association -GMP.

6. Why don't some OPC ingredient manufacturers of even big brand names post their OPC specifications on their web sites.

It is their choice to avoid competition. For example, a pine bark extract manufacturer holding the big trademark based in Switzerland (with manufacturer in UK) don't publish their specifications on their web site. But a piece of indirect information shows the content of Procyanidins > 65% without further details.

Our OPC ingredient manufacturers have the best specifications of pine bark extract OPC, grape seed extract OPC, and red wine extract OPC. They publish the OPC ingredient specifications in details on their web sites in France for OPC consumers around the world to examine and to compare.

7. Are you contradictory to yourself when you say"French grape seed extract OPC has the geographical advantage" and"OPCs, regardless of their source, possess the same biochemical activities, with only slight variations".

This is not a matter of contradiction. This is about the scientific statement on OPCs and the OPC reality on a scientific basis. The same chemicals have the same properties regardless of their sources. Only their purities count. If you claim benefits of minor components other than OPCs, you cannot do so until you establish scientific evidence. Although OPC grape seed extract contains the gallic esters of proanthocyanidins (in particular:), distinguishing grape seed extract from pine bark extract, both OPC grape seed extract and pine bark extract OPC have been demonstrated the same property of balancing blood pressure in human clinical trials. It is not clear the real difference that the gallic esters of proanthocyanidins make.

The"geographical advantage" of French OPC ingredients can be understood this way: All the major OPC ingredients were first discovered in France. And the"French paradox" is about the French heart health related to OPCs of France. Many OPC sellers claim French OPC ingredients. But the questions are whether all French OPC grape seed extracts on the market are actually made in France, whether all French maritime pine bark extracts are actually made in France, and whether all French red wine extracts are actually made in France. If you do some research on the OPC ingredient suppliers in US as we do, you would be convinced the answers for these OPC ingredient questions are no. The public OPC consumers have more confidence on the French OPC ingredients, because they have the more advanced technologies to refine OPC pine bark extract and OPC grape seed extract, and because of their longer OPC history. The red wine extract OPC is relatively less demanding on the refining technologies. Our French red wine extract is among the best based on the specifications.

8. As you said, don't trust any OPC sellers by words from their mouths. But how can I trust you about your OPC ingredients as you specified?

Please don't trust any OPC sellers, including us - Isotonic OPC Antioxidants, Inc. Don't trust any grape seed extract sellers, don't trust any pine bark extract sellers, and don't trust any red wine extract/resveratrol sellers. But please have some trust in laws!
We post the brand names of our OPC ingredients in our web sites, so that we are legally reliable for the truth of our OPC ingredients. Those owners of the OPC ingredient brand names would sue us if we use their brand names without buying their OPC ingredients.

9. Your arguments for OPCs of different sources to have analogous biological activities seem to be different from what are said by The Grape Seed Extract Method Evaluation Committee associated with Natural Product Association.

We are not aware of such a grape seed extract committee. Based on our search in the Internet for this question, we find a related web site that seems very old. It says this Committee is"Under the Auspices of NNFA Compli". One quote from that web site says"amount and types of compounds present in a particular grape seed extract can vary and is greatly influenced by the extraction process, as well as the source, variety and storage of seeds used."

This quote is correct by its direct meaning. It would be wrong if one extends this quote to say that"OPCs of different sources to have considerably different biological activities." Some people claim that one grape seed extract has the nutritional benefits for high blood pressure, while other grape seed extracts don't have. Even earlier, an OPC pine bark extract manufacturer claimed that other pine bark extracts and grape seed extracts don't have a variety of health benefits as only their own pine bark extract has.

The basis for the pine bark extract OPCs marketed as a pharmaceutical product in Europe was based on the bioavailability data of grape seed extract OPCs. This fact indicates that OPCs of different sources have the analogous biological properties. The nutritional benefits for high blood pressure are a good example to illustrate this. Now we know that different OPC pine bark extracts and different OPC grape seed extracts have been demonstrated to have the nutritional benefits for high blood pressure, contesting some earlier claims of commercial bias.

The compiling scientific data indicate that OPCs of different sources has similar health benefits, even though"amount and types of compounds present in a particular grape seed extract can vary and is greatly influenced by the extraction process, as well as the source, variety and storage of seeds used." Only the OPC purity matters the quality, while other smaller components have the negligible effects. An OPC pine bark extract and an OPC seed grape extract are both good sources of OPCs, but different greatly in their minor components. There is no scientific evidence to indicate that they differ significantly in their nutritional values other than the content of OPCs.

In addition, the committee paper also argued that"Since polymers and tannins are not well absorbed, the researchers suggest that they could exert their antioxidant activity within the digestive tract to protect lipids, proteins and carbohydrates from oxidative damage during digestion, and spare absorbable antioxidants such as vitamins E, C and beta-carotene."

Our PhD scientists think that this is wrong argument without any science backing it. The metabolism events generating free radicals are inside the cells. Free radicals are short lived due to their high activity, and cause major damages inside the cells. Polymeric proanthocyanidins as antioxidants cannot play a significant role, because they cannot cross the cellular membrane. Polymeric proanthocyanidins as the strong metal chelators, are bad to human health by interfering with mineral absorption.

10. Could you please explain more about the quality of an OPC ingredient based on its specifications?

In the past 3 years, our OPC experts - 3 PhD scientists in natural product chemistry and medicinal chemistry had the opportunity of reviewing specifications of 91 raw OPC ingredients and having 33 solid samples tested. We made our best effort in selecting the best raw OPC ingredients. Generally, the more detailed the specifications, the more reliable an OPC ingredient. At least 3 ingredients were simply specified as OPC > 95%, which by our own analysis turned out to contain OPC less than 30%, polymeric proanthocyandins (40-50%), and monomers (~20%). A lot of OPC samples with simple specifications of"Polyphenols > 95%", do not have any other details. Our tests show most samples contain OPC at 30-40%. A limited number of samples from French OPC makers gave the details how the polyphenols are broken down into subcategories of monomers, OPC, and proanthocyanidin polymers, and turned out to be reliable by our own tests. Overall, it is very hard to judge the quality if a manufacturer simply says"Procyanidins > 85%" without any detailed breakdown. It is likely something hides there under"Procyanidins > 85%" or"Polyphenols > 95%".

11. Are OPC extracts of higher OPC content necessarily better than those of lower OPC content?

My answer is this:"an OPC ingredient free of high molecular weight proanthocyanidin polymers are surely better than the one containing the polymers." The polymers must be removed to be good. A good OPC ingredient must have a declaration of the polymer content. The best OPC extract from credible French manufacturers contain up to 30% monomers (catechin and epicatechin), and 70-80% true OPC. We don't have an answer whether it is good or bad if the monomers are completely removed. It is our belief that the monomers should not be removed as they have been demonstrated health benefits, even though weaker than those of oligomers. Further, it would cost a lot more if the monomers are removed completely to make a very high content of OPC or pure OPC.