Flavonoids are molecules that regulate cell activity and help fight free radicals that cause oxidative stress in the body
In other words, flavonoids help your body function more efficiently while protecting you against toxins and everyday stressors.
According to research, a daily intake of 500 mg of flavonoids reduces the risk of cancer by 17% and cardiovascular disease by 15%. (1,2) This figure increases for smokers, alcohol users and also overweight people.
This article describes what flavonoids are, what their benefits are, and examples of foods that contain large amounts of these substances.
What are flavonoids?
Flavonoids are the largest class of plant polyphenols. There are more than 6,000 chemicals that belong to this group. The most studied subclasses are anthocyanidins, flavones, flavonols, flavonones and isoflavones. Many flavonoids are pigments that give plants their bright colors.
The first flavonoid in history was isolated from the sweet pepper or bell pepper in 1936; the main benefit found at that time was that it strengthened the walls of the blood vessels. However, the interest for this compound took off until the 1990s, after the discovery of the antioxidant properties of flavonoids; in other words, their ability to neutralize free radicals.
The most beneficial flavonoids for health are the flavan-3-ol (flavonoids), mainly epicatechin and catechin. In turn, catechin is a powerful antioxidant found in tea, Brazilian acai berries, and cocoa.
Foods that contain flavonoids by type
Quercetin is one of the most abundant flavonoids in nature. It is found in red or purple plants, some types of honey, walnuts, broccoli, cauliflower and cabbage, olive oil, and acorns. For example, talking about red wine we should mention the benefits of the flavonoid quercetin contained in black grapes.
This flavonoid helps reduce the risk of chronic vascular disease by regulating vascular permeability. Moreover, quercetin protects the brain from damage associated with local circulatory disorders, preventing the development of neurodegenerative diseases. (2)
Similar substances are found in most purple-colored fruits, vegetables, and berries, from eggplant to blueberries to red onions.
Foods with quercetin – content per 100 g:
- capers – 170-230 mg
- buckwheat – 90 mg
- sorrel – 86 mg
- radish leaves – 70 mg
- carob – 58 mg
- dill – 55 mg
- bell pepper – 50 mg
- red onion – 32 mg
- kale – 23 mg
- blueberries – 15 mg
- black plums – 12 mg
Catechins – the flavonoids in tea
Catechins are flavonoids of the flavan-3-ol type found in tea, cocoa, and some fruits and vegetables. These substances are useful for the body to reorganize the capillary network and optimize the processes of cell renewal, improving the state of the cardiovascular system. (3)
Foods with catechins – Content per 100 g:
- green tea – 10-80 mg
- black tea – 6-50 mg
- chocolate – 40-60 mg
- red wine – 8-30 mg
- apples – 10-43 mg
- apricot – 10-23 mg
- strawberries – 5-50 mg
- legumes – 35-55 mg
Anthocyanin – a purple colored flavonoid
Anthocyanins are plant glycosides related to flavonoids. They are found in plants and give red, purple and blue colors to fruits and leaves. Its consumption is associated with the regulation of blood pressure, as well as a decreased risk of developing diabetes and cancer.
Foods with anthocyanin – content per 100 g:
- acai berries – 410 mg
- black currant – 190-270 mg
- raspberries – 365 mg
- grapes – 326 mg
- blackberries – 317 mg
- cherries – 122 mg
- black rice – 60 mg
Benefits and Contraindications
Since flavonoids are an extremely broad class of substances found in plants, it is impossible to unequivocally summarize their benefits and contraindications. Some flavonoids help optimize cell metabolism, while others are toxic and not recommended.
Flavonoids with scientifically proven health benefits include catechin (the antioxidant found in tea), quercetin (a pigment that produces a red color), and anthocyanin (a pigment produces a purple or violet color). Other flavonoids are considered much less beneficial and may even have certain contraindications.
Should I take flavonoid supplements?
Although scientific research supports the beneficial properties of certain flavonoids, it is not recommended to take a specific dose in the form of dietary supplements. Furthermore, plants often contain a combination of several flavonoids and the effect of isolating just one of them is unknown.
The study mentioned above¹, which recommended a 500mg dose of flavonoids, looked at purely natural foods, noting that adherence to a healthy diet itself was clearly correlated with an increase in daily flavonoid intake.
In other words, it is enough to include green tea, natural dark chocolate, and buckwheat in the daily diet, and you should also try to consume more vegetables, fruits and purple berries. If you eat a balanced diet, supplements are not necessary.
Flavonoids are a class of plant polyphenols responsible for the color of fruits and vegetables. There are over 6000 different flavonoids found in various foods. The greatest health benefits come from catechin (an antioxidant in tea) and the pigments found in purple fruits.
Date: February 3rd, 2021
By: Gonzalo Paredes
Flavonoids in Plants May Help Protect Against Major Killers, source
Catechin in Human Health and Disease, source
Polyphenols in Chronic Diseases and their Mechanisms of Action, source
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