This is a naturally secreting hormone found in the pineal gland in the brain. This hormone is majorly in charge of the sleep- cycles of an individual. During the day, the amount of this hormone secreted is reduced which causes an individual to sleep less, however, there is an increased secretion of melatonin in the night and this helps most people sleep well. In some cases, where an individual suffers from insomnia  due to a lack of proper secretion of this hormone, melatonin supplements are prescribed to aid the sleeping patterns of the person. Apart from regulating sleep patterns, melatonin can also be used to treat some immune system problems, high blood pressure, and many more. In this article, the positive and negative effects, proper dosage, and precautions will be discussed properly.