Mechanism

Cortisol

Main glucocorticoid of the adrenal cortex. In health it has a marked circadian rhythm: a morning peak that activates us, a nighttime trough that allows sleep. It regulates blood glucose, anti-inflammatory response, blood pressure, and the stress response. Its chronic dysregulation in prolonged stress leads to burnout.

Effect by goal · level of evidence

Circadian rhythm

regulates Very high physiology (A)

Circadian basis

Peak between 6 and 9 am (CAR response), gradual decline to a nighttime trough. Disruption of the rhythm (night shifts, chronic insomnia) precedes metabolic and mood disorders.

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Chronic stress and burnout

dysregulates Very high physiology (A)

Burnout signature

In the exhaustion phase of chronic stress the rhythm flattens: low in the morning, high at night. It is the biochemical signature of burnout. Adaptogens (ashwagandha, rhodiola) help restore it.

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Anti-inflammatory response

modulates Very high physiology (A)

Basis of corticosteroids

Cortisol suppresses acute inflammation. Pharmacological corticosteroids (prednisone, dexamethasone) exploit this pathway. Chronic use causes iatrogenic Cushing's syndrome.

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Memory and hippocampus

alters Very high physiology (A)

Hippocampal atrophy

Chronically high cortisol atrophies the hippocampus and impairs declarative memory. It is one of the bases of the cognitive decline associated with stress and depression.

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Information, not medical advice. Scientific evidence reflects the quality of the studies.