Conclusions

Flavonoids originate from the phenylpropanoid pathway, a complex biosynthetic process through which plants convert simple amino acids into protective secondary metabolites. In plants, flavonoids play essential roles in stress protection, pigmentation, growth regulation and defence, underscoring their ecological and physiological importance. Upon dietary intake, flavonoid bioavailability is strongly influenced by their chemical structure, glycosylation pattern, food matrix and interactions with intestinal enzymes and gut microbiota, which collectively determine absorption, metabolism and systemic distribution. Despite generally low oral bioavailability, extensive biotransformation generates bioactive metabolites that contribute significantly to their biological effects. These processes underpin the wide range of therapeutic bioactivities attributed to flavonoids, including antioxidant, anti-inflammatory, antidiabetic, anti-aging, anticancer and cardioprotective activities, highlighting their relevance as multifunctional bioactive compounds that bridge plant metabolism and human health. By integrating plant biochemistry with clinical pharmacology, flavonoids can be transitioned from general dietary components into precise, evidence-based therapies.