The article provides an overview of dietary polyphenols, which are a diverse group of compounds found in various foods such as fruits, vegetables, wine, tea, and chocolate. These polyphenols, primarily derived from flavones, isoflavones, flavonols, catechins, and phenolic acids, exhibit a wide range of biological properties, including antioxidant, anti-inflammatory, anticancer, and cardiovascular protective effects. The biological mechanisms of action of dietary polyphenols involve their intrinsic reducing capabilities and their ability to activate endogenous defense systems and modulate cellular signaling processes such as NF-κB activation, AP-1 DNA binding, glutathione biosynthesis, and the PI3-kinase/Akt pathway. The article also discusses the classification and sources of dietary polyphenols, their bioavailability, and the potential prooxidant activities under certain conditions. Overall, the consumption of polyphenol-rich foods is beneficial for human health, contributing to the prevention of various diseases and improving overall well-being.The article provides an overview of dietary polyphenols, which are a diverse group of compounds found in various foods such as fruits, vegetables, wine, tea, and chocolate. These polyphenols, primarily derived from flavones, isoflavones, flavonols, catechins, and phenolic acids, exhibit a wide range of biological properties, including antioxidant, anti-inflammatory, anticancer, and cardiovascular protective effects. The biological mechanisms of action of dietary polyphenols involve their intrinsic reducing capabilities and their ability to activate endogenous defense systems and modulate cellular signaling processes such as NF-κB activation, AP-1 DNA binding, glutathione biosynthesis, and the PI3-kinase/Akt pathway. The article also discusses the classification and sources of dietary polyphenols, their bioavailability, and the potential prooxidant activities under certain conditions. Overall, the consumption of polyphenol-rich foods is beneficial for human health, contributing to the prevention of various diseases and improving overall well-being.