Serotonin is mainly found in the gastrointestinal tract but also plays a major role in the central nervous system. It is involved in the regulation of many psychological and physical bodily functions, such as regulating appetite, sleep, and mood. Healthy levels of serotonin have been generally linked to an overall sense of well-being .
Increased levels of serotonin are popularly associated with feelings of happiness. Low levels of serotonin have been connected to a variety of mood disorders, such as anxiety and depression . In conjunction with our catecholaminergic system, serotonin plays significant roles in our attention, working memory, and other cognitive capacities .
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