MELATONIN is a hormone (N-acetyl-5 methoxytryptamine) produced especially at night in the pineal gland. Its secretion is stimulated by the dark and inhibited by light. It main purpose is to regulate sleep cycles in mammals.
When taken as a supplement, it is used for sleep disturbances, seasonal affective disorder, neuroendocrine disorder (brain chemical imbalances) and cancer therapy.
However MELANIN is pigment produced by the skin cells in response to sun exposure.
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