In all living organisms, respiration may lead to oxidative stress, a state where increased formation of reactive oxygen species overwhelms host protection and subsequently induces DNA damage, lipid peroxidation, and protein denaturation. As a phenolic acid, chlorogenic acid occurs ubiquitously in food. It has been proven to have a number of biological effects in vitro and in vivo, including antioxidant, anti-inflammatory, and anticarcinogenic properties. Therefore, to some extent, chlorogenic acid can promote human health, and hopefully provide new methods for treatment of chronic disease. Recent studies have focused on the antioxidant properties of dietary polyphenols. The in vitro data often conflict with results obtained from in vivo studies on the antioxidant capacity of plasma or the resistance of plasma and lipoproteins to oxidation ex vivo after consumption of polyphenol-rich foods by human subjects. These inconsistencies are likely explained by the limited bioavailability of dietary polyphenols and their extensive metabolism in humans. Polyphenols exert multifaceted actions, and any clinical application using these substances should be based on a precise understanding of the physiologically relevant mechanisms.

• Youngsoo Kim(College of Pharmacy, Chungbuk National University) Corresponding author
• Sun Hong Park(Research Institute of Veterinary Medicine Chungbuk National University)
• Sang-Bae Han(College of Pharmacy, Chungbuk National University)