Melatonin is a hormone that’s produced naturally by humans, animals, and plants. It’s a neurotransmitter-like compound that’s secreted by the pineal gland, which is located in the brain. This hormone is responsible for regulating our body’s internal clock and the sleep-wake cycle. The body’s production of melatonin is most active in darkness, and least active during daylight. Its release is suppressed by light and stimulated by the dark.
