Research

Adherence

Self-reported sleep duration exceeding 8 hours per night is associated with a moderate increase in all-cause mortality, with risk ratios rising significantly for 9, 10, and 11 hours of sleep.

Aim for 7 to 8 hours of sleep. While sleeping less than 7 hours showed no significant increased mortality risk in this specific meta-analysis, sleeping more than 8 hours was associated with a moderate but significant increase in all-cause mortality. If you consistently require more than 8 hours of sleep, consider it a marker for elevated cardiovascular risk and consult a healthcare provider to rule out underlying conditions.

GoodSupportsHIGH confidence
Self-reported duration of sleep >8 hours was associated with a moderate increased risk of all-cause mortality, with risk ratio, 1.14 (1.05–1.25) for 9 hours, risk ratio, 1.30 (1.19–1.42) for 10 hours, and risk ratio, 1.47 (1.33–1.64) for 11 hours.
Chun Shing Kwok et al. · Journal of the American Heart Association · 2018

Why this rating

Large-scale meta-analysis of 74 prospective cohort studies with over 3 million participants provides high statistical power, though reliance on self-reported data introduces measurement bias.

Source

Self‐Reported Sleep Duration and Quality and Cardiovascular Disease and Mortality: A Dose‐Response Meta‐Analysis

Chun Shing Kwok et al. · Journal of the American Heart Association · 2018

Meta-analysis · 74 studiesCited 510×
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