Light at Night, Night Shift Work, and Cancer: Illustrating Cumulative Exposure to Circadian Disruption through a Thought Experiment.

Authors

Thomas C Erren, Peter Morfeld

Published in

Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology. Volume 35. Issue 10. Pages 1690-1695. Oct 01, 2026.

Abstract

Light at night (LAN) and night shift work (NSW) have been hypothesized to be carcinogenic through circadian disruption. However, cancer epidemiology examining these hypotheses in environmental or occupational settings has yielded inconclusive results. The thought experiment "The city that never sleeps" illustrates why it is reductionist to focus solely on LAN or on NSW: a link between both plausible cancer pathways could be chronodisruption (CD). CD is operationalized as the misalignment between external time (due to exposures in both the environment and the workplace) and the body's internal time; CD causes circadian disruption, conceptualized as disrupted circadian organization. CD occurs whenever individuals are awake during their biological night, which is associated with chronotype, and this can be quantified. This perspective illustrates a conceptual framework for cumulative CD doses to investigate cancer risks associated with circadian disruption and outlines six practical steps for designing studies to evaluate this concept, including a potential role of biomarkers.

PMID:
42817710
Bibliographic data and abstract were imported from PubMed on 01 Oct 2026.

Read full publication at:
Please sign in to see all details.

Stats

1-terrible, 9-excellent. How would you rate this publication? Sign in in to submit your rating.

Post a comment

You need to be signed in to post comments. You can sign in here.

Comments

There are no comments yet.