Research

Hormonal

Long sleep duration (≥9 hours per night) is associated with a significantly increased risk of coronary heart disease (RR 1.38), stroke (RR 1.65), and total cardiovascular disease (RR 1.41) compared to the reference group of 7-8 hours.

Aim for 7-8 hours of sleep per night. Consistently sleeping 9 hours or more per night is associated with a higher risk of heart disease and stroke. If you consistently need 9+ hours of sleep, it may be a marker of underlying health issues (such as depression or undiagnosed conditions) and should be discussed with a healthcare provider.

GoodSupportsHIGH confidence
Long duration of sleep was also associated with a greater risk of CHD (1.38, 1.15–1.66, P = 0.0005), stroke (1.65, 1.45–1.87, P < 0.0001), and total CVD (1.41, 1.19–1.68, P < 0.0001)...
Francesco P. Cappuccio et al. · European Heart Journal · 2011

Why this rating

Large-scale meta-analysis with high statistical power, but potential for residual confounding and lack of a clear biological mechanism for long sleep.

Source

Sleep duration predicts cardiovascular outcomes: a systematic review and meta-analysis of prospective studies

Francesco P. Cappuccio et al. · European Heart Journal · 2011

DOI 10.1093/eurheartj/ehr007

Meta-analysis · 15 studiesCited 2,139×
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DOI resolved against Crossref · corpus check 2026-06-10

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