CATEGORY: SLEEP & RECOVERY
People with more regular sleep—going to bed and waking at consistent times from day to day—had roughly a 20% to 48% lower risk of dying from any cause than those with the most irregular schedules, and this consistency predicted death risk more strongly than how long people slept, according to a large study using wearable trackers.1
How the Study Worked
Researchers analyzed more than 10 million hours of wrist-tracker data from 60,977 participants in the UK Biobank, a large health research project. Each person received a Sleep Regularity Index score—a measure of how consistent their sleep and wake times were from one day to the next. Participants were then followed for about six years on average, during which 1,859 died. The team compared people across five groups, from least to most regular, adjusting for age, sex, lifestyle, and health factors.
Regularity Outweighed Duration
Compared with the least regular sleepers, the four more regular groups had a 20% to 48% lower risk of death from any cause, a 16% to 39% lower risk of cancer death, and a 22% to 57% lower risk of death from heart- and metabolism-related causes. When the researchers weighed sleep regularity against total sleep duration, regularity was the stronger predictor of who died. In other words, the day-to-day rhythm of sleep appeared to matter at least as much as the number of hours.
What the Findings Do and Don’t Show
This was an observational study, so it points to an association between regular sleep timing and lower death risk rather than proving one causes the other. Irregular sleep can also be a sign of underlying health issues or life circumstances that affect survival. If your sleep schedule is difficult to keep steady or your rest feels unrefreshing, your health care provider can help you look into why.
Key Takeaways
- More consistent day-to-day sleep timing was associated with a 20% to 48% lower risk of death from any cause.
- Sleep regularity predicted death risk more strongly than sleep duration did.
- This is an association, not proof; a provider can help if steady, restful sleep is hard to reach.
References
- Windred DP, Burns AC, Lane JM, et al. Sleep regularity is a stronger predictor of mortality risk than sleep duration: a prospective cohort study. Sleep. 2024;47(1):zsad253. link.