“Melatonin is a hormone that is made by the pineal gland in response to cues and signals coming from the hypothalamus, the part of the brain that has what we call the central clock,” says Paolo Sassone-Corsi Ph.D., Director, Center for Epigenetics and Metabolism at University of California, Irvine. The cues telling the brain to produce (or not produce) melatonin are light and darkness. … According to Sassone-Corsi, melatonin has been identified as the key hormone regulating the sleep-wake cycle.
How melatonin can make you sleep better: what it is, how much to take, and the health benefits
Business Insider, Oct. 14, 2020
October 14, 2020