'Studies have shown that working at night damages cancer-related genes'

Studies have shown that working at night damages cancer-related genes, raising the risk of cancer.

Researchers from Washington State University and other U.S. institutions held 14 healthy adults in sleep labs for a week to simulate working overtime. Half of the participants worked at night and half during the day for comparison. After the simulation, blood was collected from the participants.

The researchers noted white blood cells in the blood sample. The rhythm of cancer-related genes in overtime workers was different from those in the daytime. In particular, genes that repair DNA damage were the problem. Daytime workers had a clear rhythm, but overtime workers's lost their rhythm due to damage.

The blood cells of night workers were also vulnerable to external stimuli. DNA damage was found to be more severe in the white blood cells of night workers when the researchers pecked radiation on blood samples. This means that overtime workers may be more vulnerable even if they are exposed to the same cancer risk.

"Working late at night can impair DNA repair and interfere with the body's anticancer activity," the researchers said. The researchers plan to expand their experiments on real workers who continue to work overtime. This is to gauge how high the risk of cancer is for workers who have accumulated DNA damage from years of overtime work.

The International Cancer Institute (IARC) under the World Health Organization (WHO) has listed overtime as a group 2A carcinogen alongside DDT, an insecticide component.