Topic
Sleep Quality
Research and strategies for improving the restorative quality of sleep beyond just hours slept.
Deep Research Articles
Research Feed
Sleep Apnea Doubles Hypertension Risk: Meta-Analysis of 45,000 People
A meta-analysis of 15 prospective cohorts (45,000 individuals) in JAMA Cardiology found that moderate-to-severe sleep apnea (AHI >=15) independently doubles the risk of developing high blood pressure, regardless of weight or age.
Optimal Melatonin Timing Depends on Your Chronotype
A new study reveals that melatonin's ideal dose and timing vary significantly by chronotype: night owls need 3mg at 2h before bed, early birds respond to 0.5mg at 1h before bed.
Consumer Wearable Sleep Staging Shows Major Accuracy Gains — But Still Biased
A Stanford-led validation study finds consumer wearables (Apple Watch S9, Oura Ring G3, Fitbit Charge 6) achieve >92% sleep-wake accuracy but over-identify N1 sleep by ~35%.
Red Light Therapy Before Bed Boosts Melatonin and Improves Sleep Onset
A randomized controlled trial shows that 15 minutes of 660nm red light therapy 1 hour before bed increases nocturnal melatonin by 27% and reduces sleep onset latency by 18 minutes in adults with delayed sleep phase.
Poor Sleep Quality Independently Predicts Elevated Cardiovascular Inflammatory Markers
A large-scale longitudinal study of 8,204 adults finds that poor sleep continuity, not just short sleep duration, is independently associated with elevated hs-CRP, IL-6, and fibrinogen levels over a 5-year period.