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Morning Light Intensity

Meaning

This refers to the measurable quantity of illumination, typically expressed in lux, that an individual is exposed to immediately upon waking and during the early hours of the day. Clinically, this is the most potent environmental cue, or zeitgeber, for setting the body’s master circadian clock in the suprachiasmatic nucleus (SCN). High-intensity light exposure soon after waking is crucial for establishing a robust diurnal rhythm, promoting daytime alertness, and ensuring timely nocturnal melatonin release. Insufficient morning light is a common contributor to circadian misalignment and subsequent hormonal dysregulation.