Research

Hormonal

Among women, both short (<5 hours) and long (≥8 hours) sleep durations are associated with adverse lipid profiles, specifically high serum triglycerides and low HDL cholesterol, forming a U-shaped risk curve relative to the 6-7 hour reference group.

For women, aiming for 6-7 hours of sleep appears to be the optimal window for maintaining healthy triglyceride and HDL cholesterol levels. Both sleeping less than 5 hours and more than 8 hours is associated with significantly higher risks of dyslipidemia. While this study is observational, prioritizing consistent, moderate sleep duration may support cardiovascular health markers.

ModerateQualifiesMEDIUM confidence
Among women, both short and long sleep durations are associated with a high serum triglyceride level or a low HDL cholesterol level. Compared with women sleeping 6 to 7 h, the relative risk of a high triglyceride level among women sleeping <5 h was 1.51... and among women sleeping ≥8 h was 1.45... the relative risk of a low HDL cholesterol level among women sleeping <5 h was 5.85... and among women sleeping ≥8 h was 4.27
Yoshitaka Kaneita et al. · SLEEP · 2008

Why this rating

Large sample size (n=3,995) and adjustment for many covariates, but it is a cross-sectional study, preventing causal inference.

Source

Associations of Usual Sleep Duration with Serum Lipid and Lipoprotein Levels

Yoshitaka Kaneita et al. · SLEEP · 2008

DOI 10.1093/sleep/31.5.645

cross_sectional · n=3995Cited 244×
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DOI resolved against Crossref · corpus check 2026-06-10

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