Polyphenols - widely used phytamines with a strong antioxidant effect
Polyphenols are found in almost all plants. They are mainly divided into phenolic acids and flavonoids. Polyphenols have many health effects, especially as antioxidants.
Polyphenols are found in almost all plants. These phytamines include many colors, smells and flavors, some fiber as well as substances with hormone-like effects, which are also called phytoestrogens. The main groups of polyphenols are phenolic acids and flavonoids. The former are mostly contained in plants as tannins, they give some of the tart taste, e.g. the black tea. Flavonoids are mostly contained as dyes (pigments) in fruits and vegetables. For example, they give cherries, grapes, apricots, medlars their red, blue and yellow colors.
Polyphenols - many health effects
Polyphenols are not essential for humans, but they have many health effects. The antioxidant functions are particularly strong. Polyphenols can help protect against cardiovascular disease, some also have anti-carcinogenic effects.
(So far) polyphenols are not considered essential nutrients, but there is no longer any doubt about their health effects according to recent research. Polyphenols generally have a wide and broad spectrum of action for our health. They can have antioxidant, antiviral, antimicrobial and anticarcinogenic effects, they can inhibit inflammation and allergies and they can modulate the immune system. A number of epidemiological studies in recent years have shown clear relationships between fruit and vegetable intake and the associated risk of heart attacks, strokes and some cancers.
If the consumption of fruit and vegetables is consistently low, the risk of these diseases increases, and if there is a high level of regular consumption of plant-based foods, the risk decreases significantly. Some flavonoids can protect blood vessels and capillaries in particular, while others are primarily antioxidant, but also anti-inflammatory or anti-carcinogenic. For polyphenols, studies of the possible health effects have so far only been carried out for a few substances.
In fruits and vegetables, phenolic acids occur mainly in the form of cinnamon and benzoic acids. They have antioxidative and sometimes anti-carcinogenic effects, and they can help protect against heart and cancer diseases. The phenolic acids include caffeinic acid from coffee and ferulic acid from cereals and rice (both cinnamic acid derivatives) and ellagic acid (benzoic acid derivative) from green tea. The heart protecting effect is likely due to the ability of some polyphenols to prevent fat oxidation and reduce platelet aggregation. Ellagic acid is believed to destroy or block genetic damage caused by carcinogens, such as from cigarette smoke or polluted air.
Flavonoids are the most common polyphenols in plants. Many of them are dyes. They have antioxidative and sometimes hormone-like effects.
Polyphenols are the most common flavonoids, often called bioflavonoids, in food. It is a group of water-soluble plant pigments that give many fruits and vegetables and herbs their bright colors. Around 4000 flavonoids are known today. They are divided into different subgroups, although the distinction is not always uniform. One type of differentiation occurs due to structural differences in six groups, which in turn comprise several substances:
|Flavonols||light yellow pigments
Quercetin in onions
Fighter oil in endive salad etc.
Catechins in red wine, apples
Epicateching gallates in green tea etc.
Hesperidin in oranges etc.
|Flavone||light yellow pigments
Apigenin in celery
Luteolin in peppers etc.
|Anthocyanins||red and blue pigments
Malvidin in blue grapes
Cyanidine in cherries etc.
Genistein and daidzein in soybeans etc.
Although structurally similar, the individual flavonoids differ in their functions. The most well-known flavonoids include quercetin from onions and genistein from soybeans. The two citrus flavonoids hesperidin and rutin are also increasingly well known today due to their health functions. Lately, the ellagic acid (epigallocatechin gallate) from green tea has received particular attention in medicine due to its anti-carcinogenic effect.
The possible health effects of polyphenols
Epidemiological studies show that eating lots of fruits and vegetables regularly can lower the risk of cardiovascular and some cancers. This is probably also due to the content of polyphenols.
- reduced risk of heart disease and stroke
- Strengthening of the blood vessels
- strengthening of the immune system (e.g. against viral infections)
- reduced risk of cancer
- Protection against age-related visual disturbances (macular degeneration, cataract)
- Relief from hay fever, sinusitis and asthma symptoms
- Relief of inflammatory processes (skin, joints, muscles)
- Relief of menopausal complaints (e.g. hot flashes)
Polyphenols - different levels in fruits and vegetables
The content of polyphenols and flavonoids can be very different in fruits and vegetables. It depends, for example, on the type of plant, the climate and the month of harvest. The flavonols occur most frequently in the types of fruit and vegetables available from us. They are particularly abundant in broccoli, endive, kale, onions, cranberries, tomato juice, red wine and black tea (over 50 mg per kg). The content in orange juice, brewed coffee, tomatoes, apples, cherries and grapes is somewhat lower (between 10 and 50 mg per kg).
Outdoor plants generally contain higher amounts of polyphenols than greenhouse plants. The distribution of the polyphenols also differs within the individual plants. They are much more concentrated in leaves and outer layers of tissue, for example in carrots, celery, horseradish, beetroot and radish, than in the roots, for example. Whenever possible, you should eat the peel of fruit and vegetables. Many flavonoids prove to be quite heat-stable during preparation.
Some only develop their full effect when they are released from the cell wall by heating. The good, old jam of compote is definitely recommended and a healthy dessert.
Polyphenols - safe phytamines in the intake
With our food we take in several grams of polyphenols every day. The regular consumption of fruits and vegetables leads to an abundance of these phytamines. Many food supplements contain polyphenols, especially the flavonoids, individually (e.g. red wine polyphenols), as a complex (e.g. quercetin, rutin and hesperidin) or in combination with other nutrients (vitamins etc.). Flavonoids work very well together with vitamin C, especially the citrus flavonoids improve its absorption in the body. The intake of polyphenols is generally considered safe, side effects are generally not known.
The exception is catechin, which may cause fever and amemia, and these side effects go away after weaning. If polyphenols are to be taken in case of illness, the treating therapist should be asked for advice. This is the best way to check whether there can be possible interactions with other drugs.