RESEARKA

What does the current evidence establish about Circadian Light Timing and human geroscience? This synthesis tests the thesis that evidence for Circadian light timing is context-dependent, separating outcome-specific signals from broader claims and identifying the evidence gaps that should bound interpretation. Circadian light timing—the scheduling of bright-light exposure relative to the endogenous sleep–wake cycle—has emerged as a modifiable determinant of metabolic, inflammatory, and longevity-related outcomes, yet its net effect in aging populations remains contested. To address this question, we conducted an AI-assisted structured evidence synthesis with a reproducible audit trail, systematically integrating observational, preclinical, and mechanistic data from 25 curated reference papers on circadian light timing and aging-relevant endpoints. Translational relevance to humans remains uncertain. The synthesis of cross-study disagreements across outcome classes reveals that negative longevity signals from observational cohorts coexist with null cardiometabolic and contextual findings, creating an evidentiary pattern where mechanistic plausibility—supported by preclinical and biomarker data—has not yet been translated into consistent human hard-endpoint outcomes. We conclude that circadian light timing likely exerts a biologically real influence on aging trajectories through immune, amyloid, and telomere-related pathways, but the human evidence is constrained by obse

Citation Support

• source_1 Hu 2025
• source_2 Cheng 2024
• source_3 Panagiotou 2024
• source_4 Shim 2024
• source_5 Windred 2024