Research

Mixed

Long sleep duration (9+ hours) is strongly associated with increased mortality risk, but this association is largely explained by confounding factors such as depression, antidepressant use, and low socioeconomic status rather than being a direct causal effect of sleep length itself.

If you consistently sleep 9+ hours, do not panic about mortality risk. Instead, investigate potential underlying causes such as depression, medication use (antidepressants/benzodiazepines), or socioeconomic stress. Treating these underlying factors is likely more impactful for your health than trying to restrict your sleep duration.

ModerateQualifiesMEDIUM confidence
Depression and low socioeconomic status are strong candidates for producing the statistical association between long sleep and mortality, either as confounders or as causal intermediates.
Sanjay R. Patel et al. · SLEEP · 2006

Why this rating

Large sample size (n=60,028) and rigorous statistical modeling (Confounding Rate Ratio), but cross-sectional design prevents causal inference.

Source

Correlates of Long Sleep Duration

Sanjay R. Patel et al. · SLEEP · 2006

DOI 10.1093/sleep/29.7.881

cross_sectional · n=60028Cited 495×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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