For several years nutrition and its effects on health have been the subject of intensive research. Fruit and vegetables in particular have proved to be a treasure trove of effective substances. They contain so-called secondary metabolites. These are not among the nutritional elements essential for life, but do play a role in several physiological processes in the body.
In so doing, many of them have a beneficial effect on health. The properties discussed range from positive effects on digestion to antioxidant, that is to say cancer-preventing, results. However, not all of these effects are sufficiently proven by scientific research.
Plants produce secondary metabolites as a protection against pests and disease, as growth regulators and as colorants. They are the reason for the wealth of different aromas and flavours to be found in fruit and vegetables.
More than 10,000 different secondary metabolites occur in foods. An estimated 1.5 grams are consumed in a mixed diet. Vegetarians can easily double that amount. The amounts of individual secondary metabolites consumed can certainly exceed those of some vitamins.