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Regularity beats duration

In 60,000 people, sleep regularity predicted mortality better than sleep length.

Galpin's practical fix for most circadian issues is a consistent wake time and morning light. The data back it: in the UK Biobank, regularity of sleep timing outperformed duration as a predictor of mortality; irregular sleepers had delayed melatonin onset and worse performance at equal total sleep; and each hour of weekday–weekend 'social jet lag' adds ~33% odds of overweight.

Trends shows your midpoint variability and social jet lag; the Signals card flags it when it's high.

Sources · 5

Sleep regularity is a stronger predictor of mortality risk than sleep durationWindred DP, Burns AC, Lane JM, et al. · 2024In ~60,000 UK Biobank participants, how regular sleep was predicted mortality better than how long it was.Irregular sleep/wake patterns are associated with poorer academic performance and…Phillips AJK, Clerx WM, O'Brien CS, et al. · 2017Irregular sleepers had delayed melatonin onset and worse outcomes even at equal total sleep.Social jetlagWittmann M, Dinich J, Merrow M, Roenneberg T · 2006Defines social jet lag — the shift in sleep midpoint between work and free days — and links it to evening chronotypes and stimulant use.Social jetlag and obesityRoenneberg T, Allebrandt KV, Merrow M, Vetter C · 2012Each hour of social jet lag was associated with ~33% higher odds of being overweight.Entrainment of the human circadian clock to the natural light-dark cycleWright KP Jr, McHill AW, Birks BR, Griffin BR, Rusterholz T, Chinoy ED · 2013A week of camping without electric light shifted the internal clock ~2 h earlier and aligned it to sunrise/sunset.

Related topics

LightRegularity & circadian

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Regularity beats duration?

In 60,000 people, sleep regularity predicted mortality better than sleep length.

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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.