Melatonin is a substance, which is normally synthesized in the brain out of the amino acid tryptophan. Normally, the concentration of melatonin depends on the daily rhythm – change of the day and the night. The organism of every human being synthesizes much more melatonin during the night. Maximal levels are reached at about 2-4 h in the morning and decrease at dawn. Melatonin concentration decreases with the progression of age.
Melatonin serves as a “marker of the biological clock” of the body and plays an important role for the normal sleep. It decreases the frequency of waking-ups during the night and improves the quality of the sleep.
It is one of the most powerful antioxidants that protect the cells against the detrimental effect of free radicals. Melatonin slows down the ageing of the cells and of the organism as a whole; it also decreases the risk of cancer and heart conditions.
After taking it, melatonin passes unchanged through the stomach and goes into the duodenum, where it is absorbed to the higher level. Around 90 minutes after the intake, its serum concentration increases and reaches steady levels for about 5 hours. Melatonin has high absorption ability and practically reaches all the cells in the body.