Bioflavonoids – All You Need to Know


In a busy and increasingly complex life, many are looking for a way to better health with a proper diet. Tables with proteins, carbohydrates, and fats, scales, and calculation of food supplements, vitamins, minerals, and liquids. Every person who is strict about eating goes through these stages. But is that enough? Is it healthy at all?

What are bioflavonoids?

Chemically, bioflavonoids are a group of polyphenolic antioxidants. Their chemical form is a derivative of glucose – they contain a glucose compound with a hydroxyl group of another substance. Today, about four thousand compounds of this type are known. It was believed that the chemical composition was the key to their antioxidant action.

Biologically, bioflavonoids are pigments of plant origin. They are associated with yellow, red, or blue pigmentation in some fruits, flowers, etc. Their pure biological significance for the plant is to attract attention – through color, and protection – bioflavonoids have the unique natural ability to protect plants from attack by certain microbes and insects.

What is their significance to humans?

Bioflavonoids and their importance in medicine have been studied recently. They were originally discovered as co-agents of vitamins that increase their biological value and especially vitamin C.

Bioflavonoids are important in preventing diabetes. Some bioflavonoids protect LDL cholesterol from oxidation. Others have a beneficial effect on diabetes-related cataracts. More and more attention is paid to their combined activities in this direction.

Bioflavonoids are most known for the fact that they bind free radicals. In colloquial language, this property is called “antioxidant”. It has been found that bioflavonoids have a more powerful antioxidant effect than the classic antioxidant nutrients such as vitamin C, E, and beta-carotene, helping to cleanse the body in the long run.

There is no established link, but it is believed that this property helps against intoxication of the body and has a prophylactic effect against some cancers.

Bioflavonoids have antibacterial and antimutagenic significance for cells in the body, which has not yet been well studied. Another known effect of bioflavonoids is the binding and excretion of metal ions.

In fact, it is the metal ions and especially the so-called “heavy metals” that are referred to as “intoxicants”. Many of them have the property to accumulate in the body, leading to malformations, changes, and mutations.

Bioflavonoids inhibit lipoprotein oxidation; as long as lipoproteins are a building block of almost the whole body and especially of the cell membrane, in this way the integrity of the cells is preserved, and self-destruction is stopped. This effect is most pronounced in blood vessels.

Bioflavonoids are thought to reduce platelet clotting and thus protect against thrombosis; Of course, their impact, in this case, should be well considered, because the reduction of blood clotting is not always beneficial to the body impact.

Some specific types of bioflavonoids have a protective effect on the stomach, for example against peptic ulcer disease. It turns out that the culprit for most allergic reactions, histamine, released by the body in certain irritations and leading to side effects is also under the influence of this complex of substances. To some extent, bioflavonoids suppress its secretion.

Bioflavonoids improve the elasticity of small blood vessels; in practice, this is prevention against diseases such as strokes and the like. This effect is undoubtedly combined with their effect in protecting cells and against thrombosis, which increases the damage to blood vessels and surrounding tissues, and is also the subject of study.

What else is good to know?

A 2007 study by the Linus Pauling Institute (the University of Oregon, which studies food) found that taking isolated bioflavonoids actually had some antioxidant and detoxifying effects, but not a direct one.

According to the study, pure bioflavonoids are absorbed only up to about 5% of the received amount. On top of that, freely in the body, the bioflavonoid is isolated and eliminated almost immediately, which increases urea and the activity of the urinary system.

It is believed that this moment leads in this case to the “antioxidant” and “purifying” effect, but to achieve it in practice no bioflavonoids are needed.

It is seen that the body accepts bioflavonoids without additional factors as external bodies, isolates them, and discards them. However, the same study goes even further.

It turns out that bioflavonoids, otherwise harmless, almost directly activate the so-called “Phase 2 enzymes.” Phase 1 and Phase 2 are not exactly our familiar enzymes (although the principle is similar) but are a protective mechanism of the body against carcinogens (cancers), toxic, radioactive, and other invasions through food.

Phase 1 enzymes are attached to the hazardous external agent. They bind to it and make it more reactive, more soluble in water, and easier to break.

Phase 2 enzymes directly attack, destroy and remove it from the body. They are considered preferable because Phase 1 enzymes are often able to make a reactive carcinogenic chemical that was not as reactive.

They are activated by the bioflavonoid and probably through food this is its real intoxicating effect – it activates the body’s defenses. Unfortunately, the mechanism is not very clear and the reason may be that the body identifies bioflavonoids as some kind of toxin.

As long as they are soluble in water, do not accumulate, are easily reactive, and are easy to remove from the body, there is no danger of intoxication or overdose – in practice, there are no known cases of overdose with bioflavonoids. But their long-term use in concentrated form may unlock processes from which the body protects itself.

Types of Bioflavonoids

Bioflavonoids are known to us along with vitamins. They are known to, for example, protect Vitamin C from oxidation and accompany it, increasing its useful functions.

Vitamin P is actually a constituent of several hundred bioflavonoids. Vitamin P accompanies vitamin C, strengthens capillary walls, reduces oxidation, and generally has most of the bioflavonoid effects discussed above.

When taking vitamin P, it is good to observe a proportion with the intake of vitamin C. Vitamin P is water-soluble. We will not be able to present all the common types of bioflavonoids. We will consider in general only three of the most common:


Widespread, in almost all complex sources of bioflavonoids, especially in citrus. It is considered the most active flavonoid. It has anti-inflammatory action. It acts on histamine as an anti-allergen.

It has an activating anti-oxidant effect and acts as a protection of vitamin C in the body. It is associated with the antidiabetic effects of bioflavonoids. It is also credited with anti-cancer protection.


Most common in cocoa, but also found in red wine and green tea, this bioflavonoid is considered key and studied for cardiac health. It also has a strong antioxidant effect; it is believed that it not only breaks down (or reacts with) free radicals but has a complete process of breaking them down and expelling them from the body.


Contained in fruits such as strawberries, cherries, blueberries, and many others, this vast group of bioactive substances is widely used in medicine. In addition to the usual antioxidant effects and removal of free radicals from the body, they have the ability to increase intracellular levels of vitamin C.

This group of substances strengthens blood vessels and helps against blood clotting. Last but not least, this group of substances inhibits the breakdown of the most important protein in the human body: collagen, which is the main component of connective tissue, bones, joints, cartilage, tendons, and skin. Substances from this group are also used in dentistry to prevent tartar.

There are a number of other bioflavonoids, such as hesperetin, rutin, malvidin, tangerine, kaempferol, and others. We cannot dwell in detail on all and their individual impacts, especially since they have not been studied in detail, but it is clear that they act synchronously and “help” each other in the final effect.

Where to get them?

Citrus – the richest source of bioflavonoids. There is a great variety. They usually contain quercetin, hesperidin, rutin, and tangerine, as well as hundreds of other less active ingredients. They increase the intake of vitamin C, which citrus fruits are rich in, protect veins and capillaries, and protect against some viruses.

Tea – black and green tea are rich in antioxidant bioflavonoids; they also affect the health of the human circulatory system. The active ingredients here are epicatechins and kaempferol. Unfortunately, the heat treatment of tea greatly reduces the activity of these ingredients.

Wine – ginger, or the “skin” of grapes is rich in bioflavonoids, including epicatechin and malvidin. As the fermentation process of red wine is closer to the storage and extraction of bioflavonoids, it is considered to be richer in them.

However, insofar as the fermentation process of wine is the fermentation of saccharides and glucose, it is not fully established how this affects glucose derivatives; in some cases, this may be harmful – for example, in many countries malvidin is considered an undesirable wine ingredient.

Cocoa – very rich in bioflavonoids, especially epicatechin, with a pronounced positive effect on the circulatory system. Unfortunately, it must be borne in mind: it only applies to the fruit of cocoa.

Chocolate is made from fats extracted from the cocoa fruit, from which bioflavonoids are deliberately released due to their intrusive taste. Consumption of chocolate is not equal to the consumption of cocoa. This also applies to the so-called black chocolate.

Small fruits – incl. raspberries, blackberries, strawberries, blackcurrants, blueberries, mulberries, etc. They contain a full range of bioflavonoids, mostly quercetin and proanthocyanidins.

A number of health and infection-preventing effects are known, and some fruits, such as mulberry, are even thought to have a direct positive effect on diseases such as diabetes, both in their fruit and leaf form.

We will find bioflavonoids in dozens of other plants and foods as exotic as ginkgo or trivial as walnuts. One thing is for sure, in their natural form they have no known harmful effects.

The conclusions are self-evident. Concentrated products with bioflavonoids may or may not be available on the market. To the extent that bioflavonoids activate the body’s toxic defenses, and in some cases are considered derivatives of the so-called. phytoestrogens, their long-term use in concentrated form is not recommended, even if no adverse effects have been described.

In their natural form, bioflavonoids are an extremely desirable ingredient in your menu. Although their overall system of effects on the body is unknown, the positive promise remains. Look for its sources and it will be respected.

Sign up for our newsletter to get the best of The Sized delivered to your inbox daily.