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Flavonoids |
What are flavonoids?
What are flavonoids?
Flavonoids form a large family of plant compounds. They determine the large variation in colour occurring in vegetables and fruit, from yellow to red and dark purple. Flavones (Latin flavus = yellow) got their name from plant compounds that were used to paint wool and cotton yellow. They are also called bioflavonoid and before vitamin P.
Until now 4000 kinds of flavonoids are described. They can be distinguished on the basis of their chemical structure in: Flavones, Flavonols, Catechins, Isoflavones, Flavonones and Anthocyans. 
Related bioactive compounds are among many carotenes, glucosinolates, organosulfides and terpenoids. The consumption of flavonoids in the western diet is low compared to Asian countries. Also because boiling and preparing the food results in a decrease in flavonoid content with 50 to 90 per cent. Hence the advice is given to eat more (fresh) vegetables and fruit. However no standard exists for the minimal quantity of flavonoids our diet should contain. |
Back to the top of this documentWhich foods contain flavonoids and bioactive compounds?
Lavons: herbs
Isoflavones: soy, legume fruits Flavonols: onions, tea, apples, red wine, broccoli, farmer cabbage Catechins: tea, red wine and fruit Anthocyans: berries (juice), red wine, blue grapes Carotenes: yellow green vegetables, are rooted, tomatoes, oranges (for Beta-carotene click here) Glucosinolates: sprouts, cabbage kinds, broccoli Organosulfides: garlic |
What is the function of this kind of bioactive compounds?
Over the last years many studies have been done to discover more about the function of these kind of bioactive compounds but far not everything is known. For a number of flavonoids it is known that they have, just as the vitamins C and E, an anti-oxidative function. They neutralize the harmful effect of aggressive oxygen molecules (free oxygen radicals or oxidants) on the cells. The in many studies found protective effect of vegetables and fruit against cancer and heart and vascular diseases possible are caused, among many other compounds, by this anti-oxidative function activity of flavonoids and some other bioactive compounds, like the carotene.
Also these compounds can work in on enzyme and hormone systems and the immune system. They can influence enzyme processes in a favourable way which play a role in cell division (cancer), blood cluttering (vascular diseases), cholesterol levels (heart and vascular diseases) and the immune system (cancer). These effects were demonstrated on laboratory animals. Isoflavones are also indicated as a plant hormones or phyto-estrogens. They resemble the human hormones based on their chemical structure. The most important groups of phyto-estrogens are the isoflavones, the lignans and the coumestans. The western population acquire little phyto-estrogens in the western diet, less than 1 milligram a day. In Asian countries, where much soy is eaten, the intake is 50 to 100 milligram a day. There are scientific indications that phyto-estrogens have a favourable influence on the prevention of breast, intestine and prostate cancer, heart and vascular diseases and osteoporosis. Phyto-estrogens bind to cells that have receptors that fit by their chemical structure (oestrogen receptors). |
Can you take food supplements with isoflavones without danger?
The common quantities of most products that are on the market nowadays, are not so different from what the average person from Asia gets via the daily portion of soy (50 to 100 milligram). Of that there are no negative effects known. On the contrary, in the Asian countries much less breast, intestine and prostate cancer occurs than in the western world.
Scientists suspect that a connection exists with the consumption of soy. In general it is recommended (unless a physician prescribes otherwise) not to use food supplements with isoflavones, that have a quantity that is above 100 milligram a day. There are no studies known that show the consequences of such high doses. Instead of food supplements also the use of soy products can be chosen. Soy products however are rich in protein which makes the already high protein consumption in our western diet yet rise further, unless they serve as a replacement of other protein sources, like meat. In food supplements alone the bioactive matters from soy are present and the proteins are omitted. For more information over isoflavones see the website: http://www.isoflavones.info Sponsored Links |