Today it is considered that the day you take in about 1 g of flavonoids . In the Far East countries consuming large amounts of tea increases the intake of flavonoids in the body. Beyond the question how many flavonoids daily replenished with food, there is the question of their absorption and bioavailability in the body, in this respect and concentration of these compounds in the blood. Add to that the fact that flavonoids have an affinity for binding with proteins, and thus the plasma proteins, the question of the concentration of flavonoids in the blood becomes more complex. Most research work related to the biological effects of these compounds in vitro whereby the excessive concentration of flavonoids, which can not be achieved in real terms in the body. In addition, numerous studies have shown rapid metabolism of flavonoids. Therefore their diet should be allocated to as many (about 5) meals a day. It is recommended that the food is varied, different colors so as to be representative of all groups of bioactive substances for the body.
The amount of polyphenols , which are consumed per day were incomplete and were obtained from the analysis of major aglikona (after hydrolysis of their glycosides and esters) in food.
Kuhnau in 1976. was calculated that the intake of flavonoids in the body through food in America, about 1 g / day. An entry consists of 16% flavonols, flavones and Flavanones, 17% anthocyanins, catechins 20% and 45% biflavona. It was found that flavonols entries 20-25 mg / day in the U.S. and Denmark.
In Italy, the values range from 5 to 125 mg / day, with a mean value of 35 mg / day (Piette, 1996).
In the Netherlands the average intake of flavonols and flavones 23 mg / day, and the main sources are tea, onions and apples. Daily consumption of anthocyanins in Finland, a country where eating is used a lot of tea, citrus fruits, berries, 82 – 200 mg. Good sources of these phenolic compounds are in the Netherlands: tea 48%, 29% onions, apples 7%, 16% other sources, and in Finland 25% of drinks (tea dominant), 67% fruit (predominantly citrus fruits), 3% of berries, 5% other sources (Heinonen, 2001).
1. Heinonen, M.: Anthocyanins as dietary antioxidants. In: Natural antioxidants and anticarcinogens in food, and disease (Nahda), Kuopion yliopisto, Finland, Helsinki, 25 (2001).
2. Kuhnau, J. (1976) The flavanoids. A class of semi-essential food components: their role in human nutrition, World Rev.Nutr.Diet., 24, 117-191.
3. Piette, P., Simonetti, P., Rogge, C.: Dietary flavonoids and oxidative stress. In: Kumpulainen JT, Salonen JT: Natural antioxidants and food quality in atherosclerosis and cancer prevention, Royal Society of Chemistry, London, 249-255 (1996).