Sleep regularity is a stronger predictor of mortality than sleep duration (2023)

Original Article ↗ Hacker News Discussion ↗

Genetic and individual variability in sleep need

  • Several participants report naturally short sleep (e.g., 4–6 hours) with good daytime functioning, sometimes linked to known mutations like DEC2.
  • Others need 8–10+ hours and feel awful below that; some can easily sleep 12 hours on days off.
  • Many stress that population-level recommendations don’t always apply to individuals.

Anxiety, sleep, and mindset

  • Some readers feel the study adds to health anxiety and makes sleep harder.
  • Others argue stressing about sleep is counterproductive; focusing on living well, social connection, activity, and not catastrophizing helped their sleep more than chasing studies or gadgets.

Correlation, causation, and confounders

  • Multiple comments highlight that sleep regularity may be a marker, not a cause, of poor health.
  • Proposed confounders: stress, low income, shift work, caregiving for children or grandchildren, chronic disease, substance use, mental health, and neuroticism/ACEs.
  • There’s debate over whether adjustments for sociodemographic and lifestyle factors are sufficient; some see such skepticism as essential scientific critique.

Study design limitations

  • Main concern: only ~1 week of accelerometer data used to predict mortality 10–15 years later.
  • People question whether that week captures chronic sleep patterns vs late-life illness.
  • The paper itself notes this snapshot as a limitation and calls for longer tracking.

Irregular schedules, circadian rhythm, and real-life constraints

  • Many describe non-24/“drifting” cycles (25–28h), night-owl tendencies, or extreme patterns (e.g., 32h awake / 12h asleep).
  • Parenting, shift work, on-call duty, and DST are cited as major disruptors; some say regularity is practically impossible.
  • A few suggest sleep irregularity may just reflect life difficulties and structural pressures.

Practical strategies people report

  • Fixed wake time (or wake window), even on weekends, is often cited as key; others say this failed them.
  • Tactics mentioned: reducing evening light/screens, exercise, avoiding alcohol, naps, power naps during extreme events, sleep apps, wearables, vibrating alarms, smart bulbs, and even pets as “natural alarm clocks.”
  • Some favor “sleep when tired” and reject rigid schedules if they chronically fail.

Magnitude of effect and tradeoffs

  • One reader reads the survival curves as only a small absolute difference over ~8 years.
  • Others argue even a few percent change in mortality from a single modifiable factor is meaningful, among many contributors to longevity.