Mixed
Long sleep duration (defined as >8 or >9 hours depending on the study) is significantly associated with increased all-cause mortality and incident cardiovascular disease, stroke, diabetes, and obesity compared to normal sleep duration.
Aim for 7-9 hours of sleep per night. If you consistently sleep more than 9 hours, be aware that this is associated with higher risks of heart disease, stroke, and mortality. Consult a doctor to rule out underlying issues like sleep apnea or depression, as long sleep may be a symptom rather than just a habit.
Long sleep was significantly associated with mortality (RR, 1.39; 95% CI, 1.31 - 1.47), incident diabetes mellitus (1.26, 1.11 - 1.43), cardiovascular disease (1.25, 1.14 - 1.37), stroke (1.46, 1.26 - 1.69), coronary heart disease (1.24, 1.13 - 1.37), and obesity (1.08, 1.02 - 1.15).
Why this rating
Large-scale meta-analysis of 137 prospective cohort studies with over 5 million participants, though observational data limits causal inference.
Source
Long sleep duration and health outcomes: A systematic review, meta-analysis and meta-regression
Maki Jike et al. · Sleep Medicine Reviews · 2017
DOI 10.1016/j.smrv.2017.06.011
More from this paper
- Long sleep duration is NOT significantly associated with incident hypertension, and evidence for depression and dyslipidemia is insufficient.Good
- There is a linear, dose-response relationship between longer sleep duration and increased mortality risk, with significant risk increasing at sleep durations >9.5 hours.Good
Related findings · Mixed
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