Melatonin, the sleep hormone is an all-natural nightcap secreted by the pineal gland located in the center of the brain. In essence, this marvel hormone is a button for one’s circadian rhythm, i.e. the internal biological clock.
However, this hormone regulates not only sleep-week cycle of humans but also play imperative role in promoting good health by boosting the immune system.
But, when it comes to a human body, everything has its downfall; just like the secretion of melatonin. Production of melatonin level declines with the process of senescence. Therefore, immunity of the old people tends to weaken gradually.