One of the effective sleep aid is the melatonin. Melatonin is a natural hormone created by the pineal gland of our brain located somewhere in the base of our brain. The most important role of melatonin is the proper regulation of the circadian rhythm of our body. It regulates the sleep and waking cycle of our body. The internal clock of our body that affects our sleeping and walking routines.

The melatonin production is encouraged by darkness and repressed by light that why it is often called "the hormone of darkness." This hormone increases in production as soon as a person's environment darkens and sleep becomes induced upon the person, necessitating him or her to lesson motor activity and allow the body to regain and refresh itself.