The Mediterranean Diet’s Antioxidants: OPCs, Hydroxytyrosol and Vitamin C

The Mediterranean Diet is known for supporting cardiovascular health and longevity. This diet contains fresh fruits, vegetables, legumes and fish, the latter being the source of the Omega-3 fatty acids EPA and DHA. The the abundant use of olive oil and the fact that Mediterranean meals are always accompanied by a good glass of red wine, make this diet mediterranean.
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The Mediterranean Diet is known for supporting cardiovascular health and longevity. This diet isn’t particularly healthy because it consists of fresh fruits, vegetables, legumes and fish, the latter being the source of the Omega-3 fatty acids EPA and DHA. These foods are part of many other healthy eating habits that are not specifically “Mediterranean.” What makes the Mediterranean Diet so “Mediterranean” is the abundant use of (virgin) olive oil as its main source of added fat and the fact that most Mediterraneans drink a good glass of red wine with their meals. Olive oil and red wine are so healthy because they contain, respectively, the essential antioxidants HydroxyTyrosol (HT) and Oligomeric ProanthoCyanidins (OPCs). Of course, there’s also plenty of vitamin C in the Mediterranean diet, but what makes HT and OPCs so interesting is that they give an extra boost to your vitamin C level by helping your body overcome its inability to produce this most essential vitamin.   

A vitamin is usually defined as an essential foodstuff of which we need only very small quantities to survive. This is why, depending on the country where you live, the official recommended daily allowances for vitamin C range from no more than 45 to 90 milligrams per day. However, according to orthomolecular health professionals, the daily amount of vitamin C that is required to provide optimal health is not in the range of milligrams but in that of multigrams. For them, vitamin C is not a micronutrient but a macronutrient. While it is true that scurvy can be prevented by relatively small amounts of vitamin C, optimal health cannot be achieved by such amounts. You do need several grams per day.

The textbooks tell us that humans are genetically incapable of producing vitamin C. It is commonly assumed that at some point in human evolution, a ‘mutation’ occurred in our genetic make-up and that this is what irreversibly incapacitated our ability to ‘manufacture’ our own vitamin C. But this ‘common knowledge’ is contradicted by research that shows that the human body hasn’t completely lost the know-how of producing vitamine C. At birth, the human liver is still capable of making considerable amounts of vitamin C. The brain of a growing fetus contains 4 to 10 times more vitamin C than the amounts usually found in adults. The umbilical cord that links the unborn child with its mother contains 4 times more vitamin C than the maternal blood. This is a strong indication that our innate capacity to produce vitamin C is still there but that, as we grow up, this ability is somehow switched off. Apparently, there is something that prevents us from using this innate knowledge. (1)

In a previous article, I introduced the readers of my blog to Epigenetica, the mysterious and ephemeral “Fairy,” who determines which strands or sections of your DNA will and which ones won’t be allowed to express themselves to influence, steer, excite or inhibit the innumerable biochemical processes that take place in our body. Think of her as the conductor who directs a symphony orchestra. To make music instead of noise, she lets the musicians know precisely when, how loud and in what mode they must play their instruments. Your DNA is the orchestra and Epigenetica is its conductor, who follows the score of optimal survival. It’s true that no one has ever met, seen or described Epigenetica. But skilled scientists are quite capable of visualizing and assessing the effects of her work by studying the “music” she produces. The fact that good amounts of vitamin C are being produced before and at birth is an indication that human DNA still knows how to make vitamin C. So, the fact that this ability is “faded out” in early life must not be attributed to a genetic, but to an epigenetic defect. For reasons yet unknown, the epigenetic conductor of our DNA shifts the key of the music of life from ‘C major’ to ‘C minor’.

Epigenetica, nutrients and botanicals

Your personal Epigenetica helps your DNA to express itself by responding to the various and many challenges that your organism has to cope with, every second of the day, every day of the year and every year of your lifetime. Epigenetica never rests. If she would fall asleep, you’d be dead. Like your DNA, Epigenetica doesn’t live in a vacuum. She’s surrounded by all the substances that you ingest and inhale and that your organism changes, glues together, breaks down, uses up, excretes or stores. In this whirlwind of biological and physical events, Epigenetica has to keep the music of life going and she can’t do that without help. Just like the cells and organs of your body, she depends on the presence or absence of essential nutrients such as beneficial botanical substances. So, in 2019, a group of scientists highly specialized in epigenetic research investigated whether 8 weeks of dietary intervention with Masquelier’s OPCs could improve the way Epigenetica conducts DNA to express itself. (2) The researchers found that regular intake of OPCs causes a significant improvement of DNA’s expression in the fields of vascular health, antioxidative capacity, blood pressure and inflammatory processes. For instance, when compared with DNA’s – disturbed ‒ expression in atherosclerotic patients, it was established that Masquelier’s OPCs push the expression in a direction opposite that of atherosclerotic patterns.

In several of my previous articles I have referred to the fact that OPCs help to improve and maintain our level of vitamin C and what their important role is in human health. It all has to do with the antioxidant capacity of OPCs and “recharging” vitamin C. Now, when it comes to the role of OPCs in that world-famous Mediterranean diet, there’s a “brother in arms.” It’s hydroxytyrosol or HT, the antioxidant found in the major constituent in the dietary traditions of the Mediterranean people: olive oil. Statistics show that Italy, Greece and Spain have the highest per capita consumption of olive oil in the entire world. In Greece, 60 % of the cultivated land is devoted to olive growing. The oil’s HT component is regarded as essential mostly because of its antioxidative capacity to scavenge free radicals. As such, HT was found to protect LDL ‒ the “good” cholesterol ‒ against oxidation and this is how HT is supposed to reduce the risk of cardiovascular disease. 

Apart from LDL protection, human studies performed with amounts of HT that can be ingested when good amounts of olive oil are used on daily basis, have shown quite some other health benefits, such as an antithrombotic (anti-blood-clotting) effect, a reduction of inflammatory markers and a reduction of blood pressure. For this reason, the Spanish researchers Eduardo Lopez-Huertasa and Juristo Fonollab decided to seek confirmation of these benefits by studying the effects of 8 weeks of daily consumption of no more than 45 milligrams of pure HT, equivalent to quantities provided by 30 grams of olive fruit or 10–15 olives. They were disappointed to find out that this low amount was insufficient to produce significant results in healthy subjects. They concluded that since the cholesterol reduction in other studies were observed at much higher doses of HT and similar antioxidants (200 – 400 milligrams per day), the daily dose used in the study must have been too low. “Indeed,” they wrote, “olive oil contains other components such as fatty acids (mainly oleic acid), which can modulate blood lipids levels. These other components may contribute to the discrepancy of results.” (3)

Fortunately there was a very interesting upside to this study. It was found that even when taken in this modest amount of 45 miligrams per day, HT was capable of significantly increasing the level of vitamin C in the participants. While the subjects showed low levels of vitamin C at baseline, i.e. when they began taking the HT, daily intake of the supplement increased the serum (blood) concentration of vitamin C by 2-fold after 4 weeks, and this remarkable increase was sustained for the following 4 weeks. These findings confirmed those obtained in a previous study in which even lower amounts ‒ 12.5 or 25 mg of HT per day ‒ were taken during 4 days by no more than 5 type I diabetes patients. These patients showed a non-significant yet observable trend to increase levels of plasma vitamin C. The Lopez-Huertasa/Fonollab study, which was carried out with more subjects and for a longer period of time, confirmed the trend seen in the previous study. Taken together, these results indicate a physiologically relevant antioxidant function for dietary HT due to its vitamin C saving effect. 

Since vitamin C must be abundantly available on a 24/7 basis to maintain optimal health, the importance of botanical substances such as OPCs and HT is evident. The above mentioned Spanish researchers even suggested that the increase of vitamin C could also affect the cooperative action of vitamin C with vitamin E (the main antioxidant of cholesterol), since vitamin C regenerates “depleted” vitamin E just like OPCs regenerate “depleted” vitamin C. This is how OPCs and HT may directly and indirectly protect LDL and HDL cholesterol against oxidation through increasing endogenous vitamin C levels. In “mediterranean” terms: red wine and olive oil form a happy couple because they provide OPCs and Hydroxytyrosol, both of which make their own independent contributions to your health and help you to overcome your inability to make vitamin C.

1. The Restoration of Vitamin C Synthesis in Humans; Thomas E. Levy, MD, JD and Ron Hunninghake, MD; Orthomolecular Medicine News Service, May 11, 2022.
 (−)-Epicatechin metabolites promote vascular health through epigenetic reprogramming of endothelial-immune cell signaling and reversing systemic low-grade inflammation. Dragan Milenkovic, Ken Declerck, Yelena Guttman, Zohar Kerem, Sylvain Claude, Antje R. Weseler, Aalt Bast, Hagen Schroeter, Christine Morand, Wim Vanden Berghe. Biochemical Pharmacolohy; November 2019.
3. Hydroxytyrosol supplementation increases vitamin C levels in vivo. A human volunteer trial; Eduardo Lopez-Huertasa and Juristo Fonollab; Redox Biology. 2017 Apr; 11: 384–389. Published online 2016 Dec 26. doi: 10.1016/j.redox.2016.12.014.