In the sphere of plant species, about 6 000 different flavonoid structures are known. These include the yellow flavonols such as quercetin and the red, blue and purple anthocyanins.
Flavonoids are found mainly in a plant’s outer layers. The skins (husks, hulls) and outer leaves from vegetables and fruits should also be eaten as much as possible. The actual flavonoid content depends on the season, since its production depends on light. Salads contain 3-5 times more flavonoids in August than they do in April.

Possible effect

  • Antioxidant (meaning, they prevent sensitive molecules’ reaction with oxygen)
  • Anti-inflammatory
  • Lower blood pressure
  • Antibiotic (meaning, they inhibit the growth of micro-organisms such as bacteria and fungi)
  • Stimulate the immune system
  • Facilitate nerve functions

May reduce the risk of:

  • Certain types of cancer
  • Cardiovascular disease
  • Thrombosis

Found in:

Flavonols: berries, apples, peppers, celery, carrots, grapefruit, oranges, red wine, tea, onions and endive.
Anthocyanins: aubergines (eggplants), berries such as cassis, blueberries and blackberries.
Quercetin: onions, kale, leeks, tomatoes and berries.

It should be noted that:

When processing apples for juice, only about 10% of the total flavonoid content is contained in the resulting apple juice, while the rest of the flavonoids remain in the pressing residue.


Recommendations for daily requirements have not yet been scientifically determined.

Phytochemicals should not be taken as isolated in tablets because this may cause undesirable side effects. The numerous other ingredients in food are most likely essential, in order that they can exert healthy effects on the body.