Optimize your nighttime environment by keeping your bedroom between 18 and 21 °C and blocking sound disturbances with earplugs or a white noise machine.

mixed

Regarding temperature, science largely validates this approach. Expert consensus, such as that from the Sleep Foundation, agrees that a cool bedroom (ideally between 16 and 20 °C)…

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Regarding temperature, science largely validates this approach. Expert consensus, such as that from the Sleep Foundation, agrees that a cool bedroom (ideally between 16 and 20 °C) supports the drop in core body temperature essential for initiating quality rest. As for silence, earplugs are a very simple and effective physical solution for blocking disruptive noise. Conversely, the use of white noise is scientifically more debated. A systematic review of 38 studies published by Pr Mathias Basner in Sleep Medicine Reviews revealed that evidence for its overall effectiveness is of low quality, noting that continuous sound stimulation may even prevent the auditory system from recovering properly. Nevertheless, small randomized controlled trials (RCT) show that white noise remains useful for masking unpredictable noise pollution peaks in urban environments.

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Claimed by Bryan Johnson (Blueprint). Noli grades the claim, never the person.

Decoded by Noli · July 13, 2026 · the original post

Noli has read similar claims

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