Abstract: An AMP-activated protein kinase (AMPK) activating agent comprises 1,2-di-O-galloyl-4,6-O—(S)-hexahydroxydiphenoyl-b-D-glucose (“GHG”) as an active ingredient. The AMPK activating agent can be a GHG-containing composition wherein the GHG is an active ingredient of the composition. The GHG-containing composition can be derived from Kenyan purple tea, whose scientific name is Camellia sinensis, variety name: TRFK306. An effective amount of the GHG can be administered to a cell to activate the AMPK. Drinks, foods, and cosmetics can have the GHG as an active ingredient.