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r/sleep@sleepreddit
I can't sleep due to my parents. Title pretty much summaries it, due to my parents I cant

what it claims

The community unanimously asserts that an excessively hot sleep environment (approximately 31°C) is severely detrimental to health and rest, and that prohibiting the use of cooling tools (fan, air conditioning) constitutes abusive or neglectful parenting.

holds up

Science confirms that thermal regulation is crucial for sleep: the body must lower its internal temperature to fall asleep, a process facilitated by a cool ambient temperature…

noli's read

Science confirms that thermal regulation is crucial for sleep: the body must lower its internal temperature to fall asleep, a process facilitated by a cool ambient temperature, ideally between 16°C and 20°C (Méta-analyse, Journal of Physiological Anthropology). Ambient temperatures well above this threshold, as mentioned here, increase wakefulness and reduce the quality of deep sleep (RCT, Science of The Total Environment). The idea that a fan causes illness is an unsupported popular belief; studies show that air circulation instead assists in the evaporation of sweat and skin cooling. If the body temperature remains too high, physiological recovery and immune functions can indeed be impaired in the long term. The community is in strong convergence in characterizing these conditions as harmful and in encouraging the young person to seek outside support.

the sources

  1. 1Lan L, Tsuzuki K, Liu YF, Lian ZW. 2017
  2. 2Brown TM et al. 2022
  3. 3r/sleep

Claimed by r/sleep. Noli grades the claim, never the person.

Decoded by Noli · July 18, 2026 · the original post

What the graded evidence says

Evidence
B
Effect
effect of ambient thermal conditions on sleep continuity/architecture; light-at-night on sleep and melatonin — heat and cold outside the comfort zone fragment sleep and reduce slow-wave/REM in experimental work; light at night suppresses melatonin and disturbs sleep
Measured on
healthy adults; thermal comfort ranges vary with age, bedding, and clothing

What’s uncertain

The 18-21°C figure is a practical guideline, not a universal set point — bedding, clothing, age, and personal preference shift the comfortable range.

r/sleep in the Register30 claims graded · solidity 81/100See their record →

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