According to a new study published in the American Journal of Epidemiology, night work can increase cancer risk in men.
This was found by a research team from Centre INRS-Institut Armand-Frappier and Centre de recherche du Centre hospitalier de l'Université de Montréal. The study is one of the first in the world to provide evidence among men of a possible association between night work and the risk of prostate, colon, lung, bladder, rectal, and pancreatic cancer and non-Hodgkin's lymphoma.
"Exposure to light at night can lead to a reduced production of the sleep hormone melatonin, inducing physiological changes that may provoke the development of tumours. This hormone, habitually released in the middle of the night in response to absence of light, plays a pivotal role in hormonal functions and in the immune system", explained Professor Marie-Élise Parent of Centre INRS-Institut Armand-Frappier, the study's lead investigator.
For this research, Dr. Parent and her team analyzed data from a study on occupational exposure and cancer that was conducted between 1970 and 1985, involving 3,137 men aged 35 to 70 years who had been diagnosed with a cancer at 18 hospitals in the Montreal metropolitan area, compared to a control group of 512 cancer-free individuals from the general population.
The epidemiological study by Marie-Élise Parent, Mariam El-Zein, and Marie-Claude Rousseau of Centre INRS-Institut Armand-Frappier and Javier Pintos and Jack Siemiatycki of Centre de recherche du Centre hospitalier de l'Université de Montréal and Université de Montréal was funded by Health Canada, the National Cancer Institute of Canada , Quebec's Institut de recherche Robert-Sauvé en santé et sécurité au travail, and Fonds de recherche du Québec - Santé (FRQS).