{Reference Type}: Journal Article {Title}: Polyphenols: Chemistry, bioavailability, bioactivity, nutritional aspects and human health benefits: A review. {Author}: El-Saadony MT;Yang T;Saad AM;Alkafaas SS;Elkafas SS;Eldeeb GS;Mohammed DM;Salem HM;Korma SA;Loutfy SA;Alshahran MY;Ahmed AE;Mosa WFA;Abd El-Mageed TA;Ahmed AF;Fahmy MA;El-Tarabily MK;Mahmoud RM;AbuQamar SF;El-Tarabily KA;Lorenzo JM; {Journal}: Int J Biol Macromol {Volume}: 277 {Issue}: 0 {Year}: 2024 Oct 29 {Factor}: 8.025 {DOI}: 10.1016/j.ijbiomac.2024.134223 {Abstract}: Polyphenols, including phenolics, alkaloids, and terpenes, are secondary metabolites that are commonly found in fruits, vegetables, and beverages, such as tea, coffee, wine, chocolate, and beer. These compounds have gained considerable attention and market demand because of their potential health benefits. However, their application is limited due to their low absorption rates and reduced tissue distribution efficiency. Engineering polyphenol-protein complexes or conjugates can enhance the antioxidant properties, bioavailability, and stability of polyphenols and improve digestive enzyme hydrolysis, target-specific delivery, and overall biological functions. Complex polyphenols, such as melanin, tannins, and ellagitannins, can promote gut microbiota balance, bolster antioxidant defense, and improve overall human health. Despite these benefits, the safety of polyphenol complexes must be thoroughly evaluated before their use as functional food additives or supplements. This review provides a detailed overview of the types of macromolecular polyphenols, their chemical composition, and their role in food enrichment. The mechanisms by which complex polyphenols act as antioxidative, anti-inflammatory, and anticancer agents have also been discussed.