Recent studies have shown that those who work overnight tend to be at an increased risk of disease, and now researchers are digging deeper to discover why this is the case.
According to a new study conducted by researchers from the University of Missouri-Columbia, sleeping and waking on the opposite schedule confuses the body’s inner clock, which disrupts cells’ natural responses and increases the risk for disease.
“We hypothesized that the messages cells produce and send each other during night work are different than those sent during the day shift,” said researcher Dr. David Gozal. “These messages come via microscopic packages called exosomes. Our study found these packages disrupt the synchronicity of the body’s systems during night shifts and cause increased insulin resistance and other health issues.”
Instability in sleeping patterns affects the body
To better understand why the body is at an increased risk of disease when consumers work the night shift, the researchers had 14 participants complete a simulated day or night shift for three days. The participants then had their blood drawn, and the researchers analyzed how the exosomes responded differently in the participants who worked the day shift versus those who worked the night shift.
Ultimately, the researchers learned that working the night shift greatly affects the body’s internal clock. Because night shift workers are on such unstable, inconsistent schedules, it’s difficult for the cells to adjust to the constant changes. This then reduced insulin sensitivity of the cells, which can increase the risk of diabetes. It also altered the internal clock of the cells, which can make the body more susceptible to disease.
“The cells in your body do not adjust as quickly as the central clock in the brain to shifts in sleep patterns,” said Dr. Gozal. “So when night-shift workers abruptly shift back and forth to daytime hours on the weekend, the cells in the body continue to send messages to each other through exosomes that lag behind the central clock. It creates a condition called ‘circadian misalignment,’ which is associated with an increased risk for cancer, diabetes, cardiovascular disease, and other illnesses.”
These findings mirror those from another recent study, which found that chronic jet lag can increase consumers’ risk for tumor growth and affect the body’s overall immune response. When consumers consistently disrupt their internal clocks, it puts a lot of stress on the body, and ultimately makes you more vulnerable to health risks.
Moving forward, the researchers hope to do more work in this area that is geared towards easing the health risks associated with working the night shift.
“By sampling the blood of workers at different times of the day and examining their exosomes, we might be able to identify whether they are misaligned,” said Dr. Gozal. “This could give us a lot of information about which workers are better suited to work night shifts. And this discovery raises the possibility of developing personalized less risk-generating shift schedules and also gene-targeted therapeutic approaches to prevent the long-term health complications of night-shift work.”