Research

Hormonal

The link between shift work and cancer (particularly breast, prostate, and colorectal) is less consistent and potentially confounded by lifestyle factors, with evidence suggesting a dose-response relationship with duration of exposure, especially for women.

For long-term shift workers, especially women, be aware of the potential increased cancer risk associated with night work. Mitigate this by minimizing light exposure during night shifts (use dim lights, blue-light blocking glasses) and maximizing darkness during daytime sleep. Regular health screenings are crucial.

ModerateQualifiesMEDIUM confidence
There is less consistent evidence linking shift work to cancer... Meta-analyses have also identified dose-response relationships between night work and prostate cancer, and between night work and colorectal cancer.
Cláudia Roberta de Castro Moreno et al. · Industrial Health · 2019

Why this rating

Based on multiple meta-analyses with varying results (some significant, some not), and large cohort studies showing dose-response but with caution regarding causality.

Source

Working Time Society consensus statements: Evidence-based effects of shift work on physical and mental health

Cláudia Roberta de Castro Moreno et al. · Industrial Health · 2019

DOI 10.2486/indhealth.sw-1

narrative_reviewCited 210×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

This is one finding among thousands. Every one is graded and traced to its source, so you can see what the evidence actually supports. Browse the research →