Melatonin And The Pineal Gland Set deep in our brains is a tiny gland called the pineal gland. This tiny gland is in charge of the endocrine system, the glandular system that controls most of our bodily functions. The pineal runs our Œbody clocks', and it produces melatonin; the hormone that may prove to be the biggest medical discovery since penicilin, and the key to controlling the aging process. The pineal gland controls such functions as our sleeping cycle and the change of body temperature that we undergo with the changing seasons. It tells animals when to migrate north and south, and when to grow or shed heavy coats. By slowing down and speeding up their metabol