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Cold Room

Thermal regulation

A - Strong EvidenceOverall rating for this intervention. See the benefits list below for per-claim ratings.

Overview

Keeping the bedroom cool (18–20°C / 65–68°F). Core body temperature must drop to initiate sleep, and a cool room passively helps that along.

How it works

Core body temperature must drop by roughly 1°C to initiate sleep. A cool ambient temperature passively extracts heat so the body does not have to work against a warm environment.

Benefits

Sleep onset: faster time to fall asleep.
A
Deep sleep: better slow-wave sleep quality.
B

Protocol

1Target 18–20°C in the bedroom.
2Use a fan or open window if your thermostat runs warm.
3Lighter bedding in summer, breathable natural fibres year-round.

Safety Profile

Risk Level

very low

Research Summary

Thermal environment is a key determinant of sleep quality in lab studies and field research. Cheap and universally applicable.

Sources

•Nighttime ambient temperature and sleep in community-dwelling older adults(2023)

Last updated: 2026-04-10

Medical Disclaimer

This is a research summary, not medical advice. Body Signals is an independent research digest — it summarises published research for informational purposes and is not a healthcare provider. Supplements like melatonin, valerian, and magnesium can interact with prescription medications — check with your doctor or pharmacist before starting any supplement. Chronic insomnia may indicate an underlying condition (sleep apnoea, thyroid dysfunction, depression) and warrants a medical evaluation.

Need professional guidance?

If sleep issues persist despite lifestyle changes, a sleep specialist or your family doctor can help rule out underlying conditions.

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