Bioflavonoids, also known as flavonoids, is a term you may have come across once or twice—especially if you’ve looked into healthy eating and dietary supplements. But what does this term actually mean?
Bioflavonoids are secondary plant compounds—more specifically, polyphenols. In the plant kingdom, they play an important role as powerful antioxidants in the defense mechanisms of many plants.
Especially in recent times, these valuable plant compounds have increasingly become the focus of scientific research. This is because antioxidants are also very valuable to us humans and play a crucial role in our immune system.
In this article, you'll learn everything you need to know about bioflavonoids and their beneficial properties. We'll also tell you which foods are particularly rich in flavonoids and what you should keep in mind to meet your daily needs.
Bioflavonoids: Roles in the Plant Kingdom
In the plant kingdom, flavonoids perform numerous important functions. These include:
- Protecting the plant from external factors: Thanks to their antioxidant properties, flavonoids act as a natural shield that protects the plant from UV radiation, pathogens, and pests.
- Determining a Plant’s Color and Scent: Whether yellow, red, or purple—flavonoids are the pigments that give plants their vibrant appearance. They are also responsible for the alluring scent of many plants, which is intended to attract beneficial insects.
- Regulation of plant growth: As important growth regulators, flavonoids influence the development of flowers, leaves, and roots.
They are found primarily in the outermost layer of plants. This is one of the reasons why the skin of many fruits and vegetables is considered particularly healthy.
Bioflavonoids and Their Effects on Humans
As you have already learned, one of the main functions of bioflavonoids is to protect plants from external influences and pests. Interestingly, these properties can, to a certain extent, also be applied to us humans.
There are now numerous studies examining the potential effects of flavonoids on the human body. These include:
- Antioxidant and anti-inflammatory effects: Bioflavonoids are powerful antioxidants. Therefore, they can help neutralize cell damage and inflammation caused by free radicals in the body.
- Immune-boosting effects: Thanks to their anti-inflammatory and antioxidant properties, flavonoids can support the immune system. The German Nutrition Society (DGE) also attributes positive effects on the immune system to them.
- Positive Effects on the Cardiovascular System: Some flavonoids may have a positive effect on cardiovascular health. Various studies* have found that they can lower blood pressure and improve blood circulation.
*Edith Cowan University. Study Finds That a Flavonoid-Rich Diet Protects Against Cancer and Heart Disease. ScienceDaily, 2019.
Bioflavonoids in Foods: Subtypes and Sources
There are 5 subtypes of flavonoids, each with its own unique structure. As a result, they are broken down differently by our bodies and also possess different properties. That’s why it’s important to ensure you’re taking the right dosage of bioflavonoids and consuming them in a balanced combination to achieve the most comprehensive benefits for your body. Here are a few examples of which foods contain which bioflavonoids:
- Flavanols: black and green tea, dark chocolate with a high cocoa content
- Flavonols: kale, onions, berries, watercress, arugula
- Flavones: parsley, thyme, chamomile, mint, celery, grapes, apples
- Flavanones: Citrus fruits such as lemons, oranges, or grapefruits
- Anthocyanins: Berries such as blueberries, raspberries, and blackberries
However, many flavonoids in food are very heat-sensitive and are quickly destroyed when cooked at too high a temperature. That’s why we strongly recommend eating fruits and vegetables as fresh as possible and using gentle cooking methods.
In addition, you might consider taking high-quality flavonoids as a dietary supplement (e.g., flavonoids in capsules) to ensure you get enough of them (daily requirement for bioflavonoids: 50 to 100 mg). For example, Pro Vitamin C —which contains the bioflavonoids quercetin, rutin, and hesperidin—or Pro Sirtusan —which contains 14 polyphenol-rich plant extracts—offer a valuable combination.
The Power of Citrus Bioflavonoids
As the name suggests, citrus bioflavonoids are a specific subgroup of flavonoids found primarily in citrus fruits —especially in their peels. Also known as citrus flavonoids, they give the fruits their characteristic tart flavor and pleasant, fresh scent. Well-known citrus bioflavonoids include:
- Hesperidin is the most common citrus flavonoid found in citrus fruits, where it is present primarily in the white layer (mesocarp) beneath the peel.
- Rutin is found in various plants, including citrus fruits, as well as apples, onions, and buckwheat.
- Naringin is found primarily in grapefruits and is responsible for their bitter-sour taste.
Citrus flavonoids, in particular, are associated with many health benefits. For this reason, they are currently the focus of numerous scientific studies and are playing an increasingly important role in the lives of many health-conscious people.
Unbeatable Synergy: Bioflavonoids and Vitamin C
You may have heard that vitamin C is especially recommended when taken together with bioflavonoids. But why is that?
In fact, there is some evidence that the two components complement and even enhance each other's effects. They also always occur together in fruits and vegetables. Here are some of the effects that are thought to result from their combination:
- Increased Bioavailability of Vitamin C: Flavonoids can help prevent the oxidation of vitamin C and enhance its activity.
- Antioxidant Synergy: Both flavonoids and vitamin C are powerful antioxidants, and both are optimally combined in our Pro Vitamin C. When combined, the effectiveness of the two components is said to be enhanced, allowing them to work more effectively at neutralizing free radicals than either substance could on its own.
- Improved blood circulation: Many flavonoids are associated with beneficial effects on the cardiovascular system, such as improved blood circulation. At the same time, vitamin C plays a role in collagen formation, which directly affects the elasticity of blood vessels. Thus, flavonoids and vitamin C can work together to support cardiovascular health.
Conclusion: Flavonoids for Our Health
The world of flavonoids opens a new and exciting chapter in science, as these fascinating plant compounds hold great promise for us. They are the best example of how nature is a rich source of wonderful possibilities. As Hippocrates once said, “Let your food be your medicine and your medicine be your food.”
Whether through the colorful variety of fruits, crisp vegetables, aromatic herbs, or targeted supplementation with dietary supplements: We want to encourage you to consciously incorporate flavonoids into your daily diet. By doing so, you’ll not only reap significant health benefits but also adopt a thoughtful, mindful approach to your diet.
Sources
- Cai, X., et al. "Bioavailability of quercetin: problems and promises." Current Medicinal Chemistry 20.20 (2013): 2572–2582.
- Ganeshpurkar, A. & Saluja, A. K. "The Pharmacological Potential of Rutin." Saudi Pharm J 25, 149–164, doi:10.1016/j.jsps.2016.04.025 (2017)
- Garg A, Garg S, Zaneveld LJ, Singla AK. Chemistry and pharmacology of the citrus bioflavonoid hesperidin. Phytother Res. Dec. 2001;15(8):655-69. doi: 10.1002/ptr.1074. PMID: 1174685.
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German Nutrition Society (Deutsche Gesellschaft für Ernährung e.V.):Phytochemicals and Health, accessed on January 30, 2024
