Bryan Johnson· Author
For that time, you want ~2 hours of REM, ~2 hrs of deep, to be up less than thirty min per night and to be asleep with a few minutes.
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The headline is broadly defensible, but the qualifications matter. Effect sizes vary by population, the strongest claims rest on shorter trials, and credible voices push back on how it's typically framed.
For that time, you want ~2 hours of REM, ~2 hrs of deep, to be up less than thirty min per night and to be asleep with a few minutes.
Every Sunday: the week’s new conflicts and verdict changes — and nothing else.
Native comments, Twitter mentions, and Reddit threads about this claim — surfaced together so the conversation isn't fragmented across platforms.
Bookmarking — the dossier-vs-overview split is the right call. Most of the time I want overview; sometimes I want receipts.
Would love a "what would change this verdict" RSS feed. Sign me up if it exists.
Sleep Quality: how fast you fall asleep, REM, Deep and Awake. Goal is <10 min, ~2hrs, ~2 hrs, and less than 30 mins.
Daily I would target: + asleep within 2-3 minutes + 2 hours of Deep + 2 hours of REM + up for less than 30 min.
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Tracking deep sleep on a wearable accurately reflects EEG-measured slow-wave sleep.
Caffeine has a half-life long enough that consumption after 2pm measurably degrades deep sleep in slow metabolizers.