Is there an Increased Risk of Breast Cancer in Night Shift Workers?

Arbaab Khan *

Department of General Surgery, Wockhardt Hospital, India.

Jaanam Altaf Khan

Department of Obstetrics and Gynaecology, Wara Hospital, Kuwait.

Mutarba Altaf Khan

Department of Obstetrics and Gynecology, Al-Adwani General Hospital, Saudi Arabia.

*Author to whom correspondence should be addressed.


In the modern 24/7 global society, the prevalence of night shift work has risen significantly, offering flexibility but also raising concerns among medical professionals and researchers about a potential link to increased breast cancer risk. This article delves into the intricate relationship between night shift work and breast cancer, examining scientific evidence, underlying mechanisms, and the imperative need for awareness and prevention. The objective of this research article is to systematically investigate and analyse existing epidemiological evidence concerning the association between night shift work and an elevated risk of breast cancer in female workers.
By examining five key articles, this literature review presents compelling results. It demonstrates an increased risk of breast cancer in women with high-intensity and long-duration night shift work.
Circadian rhythm plays a critical role in breast cancer development, involving hormone regulation, DNA repair, cell division, immune function, metabolism, light exposure, and timing of medications. Night shift work disrupts this internal clock, potentially leading to an increased breast cancer risk. Additionally, a randomized controlled trial found that melatonin supplementation significantly reduced the risk of breast cancer among night shift workers. Understanding this association is of paramount importance for public health, as it has the potential to enhance occupational guidelines, support strategies for night shift workers, and ultimately reduce breast cancer incidence among vulnerable populations.

Keywords: Breast cancer, night shift work, circadian rhythm, melatonin

How to Cite

Khan , A., Khan , J. A., & Khan , M. A. (2024). Is there an Increased Risk of Breast Cancer in Night Shift Workers?. Asian Journal of Research in Surgery, 7(1), 26–32. Retrieved from


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