Researchers at Washington State University’s Sleep and Health Sciences Lab explored the link between night shift work and various cancers. It’s well-known that those working nights face a higher risk of developing tumors.
“Growing evidence shows cancer is more common among night shift workers, which is why WHO classifies night work as probably carcinogenic.”
So, why is that?
It seems disrupting our natural body clock—meaning not syncing with day and night cycles—can trigger certain genes to become abnormally active. This raises the risk of DNA damage, which can lead straight to cancer. But let’s take it step by step!
The study found night shifts don’t just increase DNA damage; they also reduce the effectiveness of our natural DNA repair mechanisms. Each factor alone ups our cancer risk, but together, they significantly raise the odds of facing serious illness.
Researchers explained that, like the brain’s master clock, almost every cell in our body has its own biological clock. This clock regulates cell processes and genes that work differently depending on the time of day. They suspect cancer-related genes may become more active when our biological clocks get disrupted or altered.
How the experiment unfolded
The study involved 14 volunteers: half took on 3 night shifts, while the others worked regular day shifts. Researchers monitored their biological rhythms by keeping them awake for 24 hours after their shifts.
To keep things consistent, all volunteers ate the same meals on a set schedule, stayed in rooms with steady temperature and lighting. Blood samples were taken every three hours for analysis.
Disrupted biological clocks may lead to cancer
We already know white blood cells show differences in cancer-related gene activity, which the researchers focused on. They found DNA repair gene cycles were off in night shift workers, losing their natural rhythm. Night workers showed increased DNA damage and more sensitive white blood cells compared to day workers. Past studies link this cell vulnerability to higher cancer risk, confirming these findings.
“Night shift workers face serious health challenges—not just cancer, but also metabolic, cardiovascular, and mental health issues.”
“It’s high time we find solutions to this serious problem,” he added as a closing thought.
