This book presents topical research in the study of the dietary sources, properties and health benefits of flavonoids. Topics discussed in this compilation include the pharmacokinetic variability of dietary phenolic acids and flavonoids in relation to chemical and biological factors; modification of flavonoid structures by oxovanadium (IV) complexation; anti-inflammatory properties of dietary flavonoids; UV-B radiation as a powerful tool to modulate flavonoid metabolism in tomato fruits; regulation of intestinal barrier function by dietary flavonoids; anti- cancer mechanisms of flavonoids in malignant neuroblastoma and dietary sources of isoflavones and the methodology used for the analysis.