Research

Hormonal

Slow-wave sleep (SWS) exerts an inhibitory effect on cortisol secretion, contributing to the quiescent period of the HPA axis.

Focus on getting deep, restorative sleep. SWS is crucial for suppressing cortisol during the night. Disruptions to deep sleep (e.g., by alcohol or sleep apnea) may prevent this natural cortisol drop.

GoodSupportsHIGH confidence
The inhibitory effect that sleep onset seems to exert on HPA axis has been mostly attributed to SWS.
M. Balbo et al. · International Journal of Endocrinology · 2010

Why this rating

Supported by multiple studies showing temporal association between SWS and low cortisol.

Source

Impact of Sleep and Its Disturbances on Hypothalamo-Pituitary-Adrenal Axis Activity

M. Balbo et al. · International Journal of Endocrinology · 2010

DOI 10.1155/2010/759234

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DOI resolved against Crossref · corpus check 2026-06-10

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