4″-C18 EGCG is a potent inhibitor of α-amylase and α-glucosidase with IC 50 values of 3.74 and 0.81 μM, respectively. 4″-C18 EGCG inhibits carbohydrate hydrolases , reduces oxidative stress and inflammation, and exhibits antidiabetic activity. 4″-C18 EGCG also downregulates proinflammatory cytokines and is cytotoxic to primary human peripheral blood mononuclear cells (PBMCs), non-cancer cell lines 3T3-L1, and HEK 293 at 50 μM.