Temperature & air: what the research actually says

Sleep starts with a fall in core temperature, so the room's job is to let heat leave your body.

All studies · 3

Nighttime ambient temperature and sleep in community-dwelling older adultsBaniassadi A, Manor B, Yu W, Travison T, Lipsitz L · Science of the Total Environment 899:165623 · 2023Sleep efficiency was best between ~20–25 °C (68–77 °F) in older adults and dropped 5–10% as rooms warmed — cooler is better, personal range matters.The temperature dependence of sleepHarding EC, Franks NP, Wisden W · Frontiers in Neuroscience 13:336 · 2019Falling core temperature (via warm skin, cool room) is a trigger for sleep onset.Effects of thermal environment on sleep and circadian rhythmOkamoto-Mizuno K, Mizuno K · Journal of Physiological Anthropology 31(1):14 · 2012Heat exposure increases wakefulness and reduces deep and REM sleep; humidity worsens it.

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Temperature and air

Frequently asked questions

What does the research say about temperature & air?

Heat exposure increases wakefulness and reduces deep and REM sleep; humidity worsens it.

How do I track temperature & air?

SleepShred logs it in about 20 seconds a day and then compares your nights with and without it, so you see the effect on your own sleep instead of the study average.

Is SleepShred free?

No. SleepShred Pro is $4.99 per month or $29.99 per year, with no free trial and no ads. Everything stays on your iPhone.

Track it, don't guess it

SleepShred turns this research into a 20-second daily habit: log your night, see which of your own behaviours move your sleep, and screen for the disorders nobody diagnoses.

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Educational summary of published research, not medical advice. Screening scores are not diagnoses. If a score is elevated or you feel unwell, talk to a clinician.