Human bodies are programmed to stay awake during the day, when there is a natural light, and to be asleep during the night when there is no visible sunlight light. This is at night that the body produces melatonin to facilitate sleeping.
The human exposure to light and darkness regulate the sleeping process. The exposure to light stimulates a center in the brain called the suprachiasmatic nucleus to send signals to the other parts of the brain, which control the hormones in our body responsible to make us feel awake. On the other hand, the darkness causes the opposite reaction. That means that the darkness stimulates the brain to release melatonin, which is the hormone that makes us feel sleepy.
When the hormone melatonin is released (usually happens around 9 pm), the function of the other hormones that make us feel awake such as cortisol decreases. This hormone is produced by the pineal gland placed in the middle of the brain. This gland does not have any function during the day, it only activates when darkness occurs. The levels of melatonin stay elevated in the blood for 12 hours during the night.
There are millions of people worldwide who find it difficult to fall asleep during the night. There are many reasons that may be the cause for this problem and one of the reasons is that the body cannot produce enough melatonin and you cannot fall asleep on your own. Taking melatonin for sleep is one of the best ways to solve the problem when you have difficulties falling asleep at night, but this solution should be used on a short-basis.
For example, if you go through a stressful period, if you suffer from insomnia, want to overcome jet leg or you need to wake up early for school or for work but you cannot fall asleep. Melatonin supplements should be used wisely and safely. Consult a health care provided in order to help you with the right dose of melatonin.