Research

Mixed

Estimated total daily sleep duration of 6–8 hours is associated with the lowest risk of all-cause mortality and major cardiovascular events, while durations exceeding 8 hours are associated with a significantly increased risk.

Aim for 6–8 hours of total daily sleep (nocturnal plus naps) for optimal cardiovascular health and longevity. If you naturally sleep longer than 8 hours, monitor for underlying health issues, as this is associated with higher risk. If you sleep less than 6 hours, daytime napping may help mitigate some risks, but napping while getting sufficient nighttime sleep (>6h) may increase risk.

GoodQualifiesHIGH confidence
Estimated total sleep duration of 6–8 h per day is associated with the lowest risk of deaths and major cardiovascular events. ... As estimated sleep duration increased, we also noticed a significant trend for a greater risk of the composite outcome [HR of 1.05 (0.99–1.12), 1.17 (1.09–1.25), and 1.41 (1.30–1.53) for 8–9 h/day, 9–10 h/day, and >10 h/day, Ptrend < 0.0001, respectively].
Chuangshi Wang et al. · European Heart Journal · 2018

Why this rating

Large prospective cohort (n=116,632), multi-country, long follow-up, but relies on self-reported sleep duration.

Source

Association of estimated sleep duration and naps with mortality and cardiovascular events: a study of 116 632 people from 21 countries

Chuangshi Wang et al. · European Heart Journal · 2018

DOI 10.1093/eurheartj/ehy695

cohort · n=116632Cited 393×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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