Flavanols

Flavanols, which are widely distributed in plant sources, constitute an important subclass of flavonoids. Cocoa, various types of tea, and several fruits (such as apples, grapes, apricots, peaches, and blueberries) are rich in these compounds. In recent years, these compounds have attracted considerable attention due to their potential beneficial effects on cardiovascular, neurological, and metabolic health. Their biological effects arise not only from their inherent antioxidant capacity but also from their influence on cellular signaling, gene regulation, and enzyme functions. The health-promoting potential of flavanols is closely linked to their chemical structure and metabolism. While early research emphasized their antioxidant role in neutralizing reactive oxygen species, recent findings have revealed more complex physiological effects involving interactions with endothelial cells, gut microbiota, and the immune system. This chapter provides a comprehensive evaluation of the chemical structure, dietary sources, and bioavailability of flavan-3-ols, as well as their biological activities, including antioxidant, cardiovascular, anti-inflammatory, neuroprotective, anticancer, and metabolic regulatory effects. The chapter concludes with an examination of clinical evidence supporting these health benefits and a discussion of future research directions.