Melatonin is a compound which is obtained from the amino acid tryptophan. In the human body the man site of production is the brain where it is released from the pineal gland. The pineal gland is a pea sized gland located in the midbrain. Melatonin is mainly concerned with the sleep cycle. It promotes sleep. Its production starts in the evening and reaches a peak at midnight. Thereafter, it starts falling. Hence, melatonin has been called the hormone of darkness. People with severe brain injuries have difficulty in going to sleep. Brain injury decreases the production of melatonin, thus, indicating the connection between melatonin and sleep.
Light inhibits the secretion of melatonin. Thus, longer the lights are switched on, lesser would be the melatonin secretion. This is precisely why people are advised not to watch TV just before going to bed. People also tend to sit in front of the computer and indulge in various activities. These habits disrupt the normal pattern of melatonin release and interfere with the circadian rhythm. This light-interrupted decrease in melatonin secretion has grave health implications for people working through the night. The disruption of normal sleep patterns can give rise to diseases which are common in people acquiring sleep debt. Type 2 diabetes is a classical example. Sleep deprivation can also predispose to heart disease and neurodegenerative diseases like the Alzheimer’s disease.
Melatonin is also present in a number of fruits and vegetables. For example, it is present in mustard, almonds, sunflower seeds, berries, cherries and cardamom. Melatonin can also act as an antioxidant. Thus, the consumption of fruits and vegetables containing melatonin can boost the antioxidant capacity. Melatonin is also present in red grapes. Therefore, the consumption of red wine at late evening or night may have an additive effect as it supplements the action of the melatonin already present in the system. Thus, red wine can act as sleep promoter.
Obesity increases the risk for heart disease. This is mainly because of rise in the blood levels of LDL cholesterol and triglycerides. Experimental studies have suggested that consumption of melatonin containing vegetables and fruits can prevent further weight gain and also decrease the cholesterol and triglyceride levels. This action is probably related to the antioxidant activity of melatonin.