Melatonin is a neuropeptide that is responsible for circadian rhythms, helping to fall asleep and wake up (for which it was called the “sleep hormone”). He is also involved in the regulation of body temperature, reproductive processes and aging processes, slowing them down and increasing life expectancy, for which he also received the name “hormone of youth.” And the influence of the hormone is not limited to this: melatonin, its functions in the body are being actively studied. There is evidence that this compound also has anti-stress and anti-cancer effects, and its deficiency seriously impairs well-being.
Sleep hormone: how is it synthesized?
Although melatonin has come to be called the “sleep hormone” because it stimulates the desire to fall asleep and then wake up, it is actually responsible for the frequency of sleep, and is not a natural sleep aid.
In a healthy adult, 30 mcg of melatonin is produced daily, and at night it is almost 30 times more than during the day, and the highest amount of this hormone is synthesized at the age of three years! The peak of daily synthesis is 2 am.
About 70% of melatonin in the body is produced in the dark, and in the light of its synthesis is sharply reduced. When the sun’s rays begin to break into the room (or a lantern is turned on at the window), its amount decreases, and awakening occurs.
During the day, in the same pineal gland, where melatonin is actively synthesized at night, the secretion of serotonin, the “hormone of happiness and pleasure,” is activated. It is the basis for the synthesis of melatonin, serotonin itself is produced in bright light during the transformation of tryptophan. We get this amino acid from food.
If enough serotonin is produced, then melatonin will be enough.
Melatonin is also produced by the gastrointestinal tract, kidneys and liver, regardless of lighting, but its main supplier is the pineal gland of the pineal gland.
Beyond the biological clock: functions of melatonin in the body
Some of the functions of melatonin are directly related to the regulation of circadian rhythms: if you sleep “wrongly”, then anxiety and depressive states develop, the immune and endocrine systems suffer, and the level of the hormone ghrelin increases, which increases appetite.
This is not just due to lack of sleep. The same effects are observed during night work, shifted schedules of sleep and wakefulness. And one of the reasons is melatonin, whose functions are not limited to the regulation of biological rhythms.