Research

Mixed

Better self-reported sleep quality is associated with better mental health outcomes, specifically showing a U-shaped relationship where both short and long sleep durations correlate with higher depression and anxiety.

Prioritize sleep quality over just duration. If you are sleeping 7-9 hours but still experience high anxiety or depression, your sleep efficiency or continuity may be poor. This study suggests that poor sleep quality is strongly linked to mental health issues, regardless of age. Aim for consistent, efficient sleep rather than just time in bed, and be aware that both sleeping significantly less or significantly more than average can negatively impact mental well-being.

GoodQualifiesHIGH confidence
we observe U-shaped associations between sleep duration and mental health (depression and anxiety) as well as self-reported general health, such that both short and long sleep were associated with poorer outcomes.
Andrew Gadie et al. · BMJ Open · 2017

Why this rating

Large cohort (n=2406), healthy population, use of validated scales (PSQI, HADS), and Bayesian regression providing strong evidence for the null in other domains strengthens the specificity of this positive finding.

Source

How are age-related differences in sleep quality associated with health outcomes? An epidemiological investigation in a UK cohort of 2406 adults

Andrew Gadie et al. · BMJ Open · 2017

DOI 10.1136/bmjopen-2016-014920

cross_sectional · n=2406Cited 208×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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