Research

Hormonal

Dim light at night disrupts circadian clock gene expression in the hypothalamus and liver, attenuating the amplitude of Per1, Per2, and Rev-Erb rhythms.

Your internal body clock relies on darkness. Dim light at night can weaken the signals that regulate your metabolism, even if you don't feel tired.

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exposure to ecologically relevant levels of dim (5 lux) light at night altered core circadian clock rhythms in the hypothalamus at both the gene and protein level.
Laura K. Fonken et al. · Journal of Biological Rhythms · 2013

Why this rating

Detailed molecular analysis with clear statistical support.

Source

Dim Light at Night Disrupts Molecular Circadian Rhythms and Increases Body Weight

Laura K. Fonken et al. · Journal of Biological Rhythms · 2013

DOI 10.1177/0748730413493862

mechanism_only · n=120Cited 306×
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DOI resolved against Crossref · corpus check 2026-06-10

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