Cortisol awakening response

Common card · No. 348854

The cortisol awakening response (CAR) is an increase between 38% and 75% in cortisol levels peaking 30–45 minutes after awakening in the morning in some people. This rise is superimposed upon the late-night rise in cortisol which occurs before awakening. While its purpose is uncertain, it may be linked to the hippocampus' preparation of the hypothalamic-pituitary-adrenal axis (HPA) in order to face anticipated stress. Other research has challenged the idea that this elevation in morning cortisol is specifically linked to the onset of waking.

Read on Wikipedia · Image Ben Mills, Public domain