Research

Mixed

Both short sleep duration (≤5 hours) and long sleep duration (≥9 hours) are independently associated with a higher risk of cardiovascular disease (CVD) compared to 7 hours of sleep.

Aim for 7 hours of sleep per night to minimize cardiovascular risk. Both sleeping less than 5 hours and more than 9 hours is associated with a significantly higher risk of heart disease and stroke. If you consistently need 9+ hours of sleep, consult a doctor to rule out underlying conditions like sleep apnea, as this may be a marker for health issues rather than just a preference.

ModerateSupportsMEDIUM confidence
Compared with a sleep duration of 7 h (referent), the multivariate odds ratio (95% confidence interval) of CVD was 2.20 (1.78, 2.71), 1.33 (1.13, 1.57), 1.23 (1.06, 1.41), and 1.57 (1.31, 1.89) for sleep duration ≤ 5 h, 6 h, 8 h, and ≥ 9 h.
Charumathi Sabanayagam et al. · SLEEP · 2010

Why this rating

Large, nationally representative cross-sectional study with robust multivariable adjustments, but cross-sectional design limits causal inference.

Source

Sleep Duration and Cardiovascular Disease: Results from the National Health Interview Survey

Charumathi Sabanayagam et al. · SLEEP · 2010

DOI 10.1093/sleep/33.8.1037

cross_sectional · n=30397Cited 369×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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