Andrew Huberman· PhD
When you sleep, heart rate variability increases, right? Parasympathetic tone increases. Sympathetic nervous system goes very quiet.
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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.
When you sleep, heart rate variability increases, right? Parasympathetic tone increases. Sympathetic nervous system goes very quiet.
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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.
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