Research

Hormonal

Specific cytokines (IL-1, TNF, IFN) produced during the immune response act on the brain to increase non-REM sleep duration, demonstrating a bidirectional communication between the immune system and sleep regulation.

Your immune system uses chemical signals (cytokines) to tell your brain to sleep more when you are sick. This is a biological command to prioritize healing over other activities.

StrongSupportsHIGH confidence
certain cytokines affect sleep, such as IL-1, which, when administered intracerebroventricularly into rabbits and rats, increases the duration of non-REM sleep. This effect is abolished when IL-1 antagonists are given [29–31]. Administration of the cytokines TNF- and IFN- has the same effect as IL-1 [32–34].
Elizabeth Ibarra‐Coronado et al. · Journal of Immunology Research · 2015

Why this rating

Strong mechanistic evidence from animal studies showing direct causal links between cytokine administration and sleep changes.

Source

The Bidirectional Relationship between Sleep and Immunity against Infections

Elizabeth Ibarra‐Coronado et al. · Journal of Immunology Research · 2015

DOI 10.1155/2015/678164

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

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