Melatonin is the hormone that regulates sleep and rest. It helps maintain and restore the correct balance between sleep and wakefulness. When the levels of melatonin we produce are low, episodes of insomnia, early awakening, and difficulty falling asleep occur. Melatonin is a hormone produced by our pineal gland located in the brain. The action of this neurotransmitter is similar to that of a sleeping pill, which is why it is also called the "sleep hormone." It is thanks to melatonin that we are able to have restorative sleep. The production of this hormone in the body is linked to light exposure. It begins in the early evening hours and plays an important relaxing role at the time of falling asleep.