Every output names at least one verified PubMed source.
Dautovich ND, et al. A systematic review of the amount and timing of light in association with objective and subjective sleep outcomes in community-dwelling adults. Sleep Health. 2019;5(1):31-48. PMID 30670164 Systematic review of light amount and timing versus sleep outcomes. · weight 1.0 · Brighter morning light is associated with earlier sleep timing and better self-reported sleep; brighter evening light shifts sleep later and is associated with worse self-reported sleep.
Menezes-Júnior LAA, et al. The role of sunlight in sleep regulation: analysis of morning, evening and late exposure. BMC Public Health. 2025;25(1):3362. PMID 41053799 Cross-sectional/observational population study of sunlight exposure timing and sleep. · weight 0.5 · Timing of sunlight exposure is associated with sleep measures; observational design, so direction of causation is not established.
Limits: Self-reported minutes are rough, and the link between logged exposure and sleep quality here is correlational within your own week, not causal evidence.
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