Skip to main content

Nocturnal Cortisol Suppression

Meaning

Nocturnal Cortisol Suppression refers to the necessary and physiological reduction in the secretion and circulating concentration of cortisol that occurs during the later hours of the night, reaching its lowest point around the middle of the sleep cycle. This suppression is a vital component of the healthy circadian rhythm, permitting the restorative processes of sleep and allowing for the pulsatile release of anabolic hormones like Growth Hormone. A failure to achieve adequate suppression is a clinical indicator of chronic stress or HPA axis dysregulation. Optimal suppression is essential for metabolic and physical recovery.