Recent research clarified that mast cells are controlled by their internal clock—which is regulated by a specific set of clock genes—as well as external factors such as light sensed by the suprachiasmatic nuclei, hormonal status, or diet.

The production of histamine by bacteria in the human gut influence the immune response, although the major source of histamine is food. The large spectrum of histamine effects on a number of cellular processes results in various gastrointestinal disorders including food allergy, histamine intolerance, irritable bowel syndrome, and inflammatory bowel disease, among others.