cortisol

n. A glucocorticosteroid hormone released from the adrenal cortex. Cortisol enhances sugar metabolism, thus contributing to increased energy levels. Cortisol also suppresses the immune system via a decrease in lymphocytes, which slows the formation of antibodies. Cortisol also directly affects neurons within the central nervous system, in particular cells in the hypothalamus associated with flight-or-fight responses and cells in the hippocampus associated with the consolidation of memory. Cortisol is known as the “healer-killer”： low or acute levels of cortisol are useful in healing and in necessary response to stress; high or chronic levels lead to neural and tissue damage and decreased immune function. The secretion of cortisol increases in response to both positive and negative stressors, emotional and physical anxiety, and trauma. Cortisol levels may be measured noninvasively by careful analysis of saliva.

- VS