Flavonoids: a new biomarker for intake of fruits and vegetables

The primary cause of death in Denmark is cancer and heart disease. Many studies have shown that a diet rich in fruits and vegetables can prevent development of these diseases, but it is yet unclear what compounds in fruits and vegetables that have the disease preventive properties.

The use of biomarkers in population studies is a new tool to study the intake of individual compounds in our diet. Traditionally only dietary records and interviews have been used to estimate the intake of certain foods, but the biomarkers can give us more exact measures of the ingested diet.

Carotenoids are a group of fat-soluble pigments widely distributed in nature. They are especially abundant in yellow-orange fruits and vegetables and dark green, leafy vegetables. Therefore, plasma carotenoids are often chosen as biomarker for intake of fruits and vegetables.

In the present study we investigate the validity of a new biomarker for intake of fruits and vegetables. The biomarker is a measure of the content of flavonoids in urine samples collected from 250 subjects participating in "Inter99". Flavonoids is a group of polyphenols found in fruits and vegetables, that are thought to have health preventive properties. The Inter99 study is a population study conducted by Centre for Prevention and Health, Glostrup University Hospital. We participate in the validation of the food registration used in this study by use of the carotenoid and flavonoid biomarkers.