Pyrroloquinoline quinone (PQQ) is a fascinating and bioactive quinone compound that has garnered significant attention in the fields of nutrition and health. Discovered initially as a cofactor for certain enzymes, PQQ's potential benefits extend far beyond its enzymatic roles. This compound is naturally occurring in a variety of foods, including fermented products like miso and natto, as well as in fruits and vegetables such as kiwi and green peppers. With an impressive array of biological activities, PQQ stands out as a potential ally in promoting overall health and well-being.