Known and used for its properties that regulate sleep wake rhythms, and for reducing the effects of jet lag, melatonin is an extremely old molecule found in both animals and plants.
Where to find melatonin
Melatonin is a molecule that can be found in several forms of life in nature. It can be found in every living being, from the animal and the plant kingdoms.
Every organism uses melatonin, whether animal or plant, including many plants used as food.
Melatonin is a very old molecule, and many studies agree in placing its origin at the initial stage of biological evolution. It is thought that it was already present during the period of big changes that led to the appearance of life on Earth. Melatonin, in fact, seems to be one of the factors that made the progressive adaptation to environmental conditions possible, which led to the birth of the first forms of life.
Composition of melatonin
Its molecular name is N-acetyl-5-methoxy-tryptamine and comprises an acetyl group and a methyl group. It is mainly synthesized by the pineal gland, but other organs and tissues can partly produce it: the retina, for example; intestinal mucosa; megacaryocytes and platelets.
In addition to being the organ that produces it, the pineal gland also plays the part of inhibiting and favoring production as light changes during the hours of the day. The pineal gland is influenced by the retina, or rather by the detection of light perceived from outside. When we are exposed to light sources (sunlight, but also light from artificial sources), melatonin production is inhibited, and remains at very low levels. During darkness it decreases and varies during the night.
Effects of melatonin
Melatonin has multiple effects. From a molecular structure point of view, its ancient origin and cyclic structure allow for several hypotheses. What we can say today is that this molecule – that seems to have made life on earth possible, therefore so precious in many respects – favors the sleep-wake rhythm. The endogenous (internal, by the pineal gland) production of melatonin during the night plays the vital role of helping to prepare the body for rest.
The exogenous (through food supplements) taking of melatonin supports this process.
It reduces the time required to fall asleep
Observations and studies conducted in this field have shown that the highest levels of melatonin are found at a precise point of the night. This nocturnal production peak generally takes places between one and three am, during the deep sleep stage, and is a message that persuades the body to abandon itself to rest, which is necessary to recover the energy spent during the day, and for the restoration processes involved in the body regenerating and repairing itself.
The exogenous taking of melatonin helps this process by reducing the time taken to fall asleep, in both normal conditions, and when (especially when) achieving this stage is hindered by stress, a long exposure to light sources and many other factors.
It regulates the biological rhythm of sleep and wakefulness
Melatonin production is influenced by the fact that cells in our body are assigned to recognize light. Internal melatonin synthesis is inhibited by light. Therefore, when we move through various time zones, due to work or leisure travel, our sleep-wake rhythms may suffer various degrees of disturbance.
In these cases, the exogenous taking of melatonin helps to keep the body synchronized with the physiological cyclic nature of our biological rhythms that regulate our sleep and wake stages.