Artificial Light at Night, Sleep Disruption, and Liver Health: Implications for MASLD Pathogenesis.
Damaris Guadalupe Nieva-Ramírez1, Misael Uribe2, Natalia Nuño-Lámbarri1,3
1Traslational Research Unit, Medica Sur Clinic & Foundation, Puente de Piedra 150, Toriello Guerra Tlalpan, Mexico City 14050, Mexico.
International Journal of Environmental Research and Public Health
|November 27, 2025
Summary
Artificial light at night (ALAN) disrupts circadian rhythms and melatonin, contributing to liver and metabolic diseases like metabolic dysfunction-associated steatotic liver disease (MASLD). Reducing light exposure can improve metabolic health.
Area of Science:
- Environmental Health
- Chronobiology
- Hepatology
Background:
- Artificial light at night (ALAN) is an emerging environmental factor impacting human health.
- Circadian disruption from ALAN is linked to various metabolic disorders.
- Metabolic dysfunction-associated steatotic liver disease (MASLD) is a growing public health concern.
Purpose of the Study:
- To review and synthesize evidence on ALAN's role in liver and metabolic health.
- To critically evaluate the link between nocturnal light, circadian disruption, and MASLD.
- To explore the mechanisms underlying ALAN's impact on hepatic metabolism.
Main Methods:
- Narrative review of experimental and epidemiological studies.
- Literature search across major scientific databases (PubMed, Scopus, Web of Science, Google Scholar).
- Inclusion of studies from 1980-2025 focusing on ALAN, circadian disruption, and MASLD.
Main Results:
- Blue-enriched light suppresses melatonin and desynchronizes circadian clocks.
- ALAN promotes insulin resistance, oxidative stress, and hepatic steatosis.
- ALAN affects gut microbiota and intestinal permeability, implicating a light-gut-liver axis in MASLD.
Conclusions:
- ALAN is a significant environmental determinant of liver and metabolic health, contributing to MASLD.
- Mitigation strategies involving lighting design and sleep hygiene are crucial.
- Public health initiatives should address ALAN's metabolic impact.
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