Can an Anti-inflammatory Diet Offset the Increased Cancer Risk Associated with Night Shift Work?

Introduction: Night shift work has been associated with increased risk of breast, prostate and colorectal cancer. Recent literature shows that shift workers may report poorer food choices, irregular mealtimes and more pro-inflammatory diets than day workers. We aimed to study the combined effects of night shift work and dietary inflammatory potential on risk of four common cancer types.

Methods: We used data from the MCC-Spain study, a population based multi-case- control study on 4 tumors, including 4325 cancer cases (colorectal, breast, prostate, stomach) and 3560 population controls recruited between 2008–2015 in 12 regions of Spain. Based on a food frequency questionnaire assessed around study recruitment, we calculated the energy-adjusted dietary inflammatory index (E-DII). We used the median E-DII among controls (-0.564) to define anti- and pro-inflammatory diet. We collected night shift work information using lifetime occupational history, including exact work hours, cumulative night shift work duration (years), night shift work frequency (average number of night shifts/month) for each job held for >1 year. Night shift work was defined as at least 3 hours of work between midnight and 6:00. Unconditional logistic regression was used to estimate Odds Ratios (OR) and 95%CI for the joint association of E-DII (anti- vs pro- inflammatory diet), and night shift work (never vs ever never), night shift work duration (<15 years vs ≥15 years) and night work frequency (<3 vs ≥3 night shifts/month) for each cancer type, adjusting for potential confounders

Results: Night shift workers were more likely to report a higher dietary inflammatory potential (higher E-DII), and a higher intake of calories, red meat, alcohol and sugar compared with day workers. Compared with day workers with anti-inflammatory diet, a pro-inflammatory diet in night shift workers was associated with elevated odds of colorectal (OR 1.59; 95%CI [1.28–2- 01]), breast (1.27 [0.91–1.79]), prostate (1.31 [0.99–1-73]) and gastric cancer (1.74 [1.32–2.31]). An anti-inflammatory diet in night shift workers was not associated with breast cancer (1.08 [0.80–1.45]) among those with <15 years of night shift work. However, long-term night shift work (≥15 years) was associated with 3 times greater odds of breast cancer in both anti- and pro-inflammatory diet groups, compared with day workers. Night workers who followed an anti-inflammatory diet did not show increased breast cancer odds (1.02 [0.66–1.55]) when employed in shift schedules with <3 nights/month, though this protective effect diminished (1.78 [0.86–3.79]) among shift workers with ≥3 nights/month.

Conclusion: In a large case-control study, night shift work and a pro-inflammatory diet were jointly associated with higher risks for cancer. An anti-inflammatory diet appeared to mitigate the increased breast cancer risk in night shift workers with low shift work duration and intensity, suggesting that dietary modifications could be a potential strategy to offset some of the adverse effects of night shift work. Support: We would like to acknowledge the rest of the co-authors that contributed to this manuscript: Manolis Kogevinas (ISGlobal, Barcelona, Spain), Barbara Harding (ISGlobal, Barcelona, Spain), Kurt Straif (ISGlobal, Barcelona, Spain), Jose Juan Jimenez- Moleon (Department of Preventive Medicine and Public Health, University of Granada, Granada, Spain), Ana-Molina Barcelo (Cancer and Public Health Area, The Foundation for the Promotion of Health and Biomedical Research of Valencia Region (FISABIO), Rafael Marcos Gragera (Epidemiology Unit and Girona Cancer Registry, Oncology Coordination Plan, Department of Health, Autonomous Government of Catalonia, Catalan Institute of Oncology Girona, University of Girona, Girona, Spain), Adonina Tardon (University Institute of Oncology (IUOPA), University of Oviedo, Oviedo, Spain), Juan Alguacil (Centro de Investigaciónen Recursos Naturales, Salud y Medio Ambiente (RENSMA), Universidad de Huelva, Huelva, Spain), Nuria Aragones (Public Health Division, Department of Health, Madrid, Spain) and Beatriz Perez-Gomez (National Center for Epidemiology, Carlos III Institute of Health (ISCIII), Madrid, Spain).

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Artikel online veröffentlicht:
08. Oktober 2025