Enhancing Polyphenol Bioavailability

Polyphenols are a diverse group of bioactive compounds found abundantly in plant-based foods such as fruits, vegetables, tea, and wine. Their health-promoting effects stem from potent antioxidant and anti-inflammatory properties, making them valuable agents in preventing and managing chronic diseases including cardiovascular disease, cancer, diabetes, and neurodegenerative disorders. The major classes - flavonoids, phenolic acids, lignans, and stilbenes - each exhibit unique pharmacological actions mediated through modulation of signaling pathways, gene expression, and cellular interactions. Despite their therapeutic potential, polyphenols suffer from inherently low bioavailability due to poor solubility, instability in the gastrointestinal tract, rapid metabolism, and limited absorption. This chapter explores the multifactorial aspects influencing polyphenol bioavailability, including their physicochemical properties, metabolism, gut microbiota interactions, and host-specific variables such as age, genetics, and dietary context. It further reviews advanced strategies to enhance bioavailability, including nanoencapsulation, lipid and polymer-based delivery systems, cyclodextrin complexation, prodrug approaches, and bioenhancers. Among these, nanotechnology has emerged as a promising tool, offering improved stability, targeted delivery, and sustained release. Collectively, these innovations represent a paradigm shift in maximizing the clinical utility of polyphenols, bridging the gap between nutritional science and pharmaceutical application.