Workers Health & Safety Centre

Women working longer hours are at increased risk for diabetes, says new research

Working beyond a 40-hour work week leads to higher rates of type 2 diabetes in women compared to those working fewer hours, according to a recent Canadian study.
The study found the risk for diabetes becomes significantly greater (by 63 per cent) for women working in excess of 45 hours each week compared to those working between 35 and 40 hours per week. No excess risk was seen among women working 30 to 40 hours per week or men in general regardless of their hours.  
Researchers evaluated the relationship between work hours and the incidence of diabetes for more than 7000 men and women workers from across a wide cross-section of industries and occupations in Ontario. These workers had never been diagnosed with diabetes. Over the 12-year study period one in ten of these workers were diagnosed with diabetes.

Long hours, stress and diabetes

Though this study did not seek to uncover cause and effect, it cited a growing body of research that suggests long work hours cause a stress response that might lead to sleep disruption, hormone imbalances, insulin resistance, glucose intolerance and obesity—all contributing factors for diabetes.
Also cited is research that might explain the gender difference. This research suggests unpaid work at home for women may also be a factor leading to excess stress, ill health, and the potential for diabetes. This study looked at paid and unpaid hours spent on the job, but not unpaid hours performed outside of work.
“If you think about all the unpaid work they (women) do on their off-hours, like household chores for example, they simply do more than men, and that can be stressful, and stress negatively impacts your health,” Mahée Gilbert-Ouimet, lead author and postdoctoral fellow at the Institute for Work and Health (IWH).
Gilbert-Ouimet also suggested the ongoing struggle to achieve equal pay for equal work might further add to stress and diabetes risk in working women. “Even when men and women do similar work, women earn less. Of course, that would impact women’s health. Think about the stress of working harder and getting less for it.”

Prevention through workplace intervention

Although this study did consider risk factors for diabetes external to work, including smoking, exercise, alcohol consumption and obesity, it found the impact to be minimal. This suggests prevention efforts need to focus on hours of work and not the behaviour of individual workers. The authors of this study concluded: “Identifying modifiable risk factors such as long work hours is of major importance to improve prevention and orient policy making, as it could prevent numerous cases of diabetes and diabetes-related chronic diseases.”
Lead author Gilbert-Ouimet was even more specific, stating a “regular workweek of 35 to 40 hours might be an effective strategy for preventing diabetes among women. ”According to data from Diabetes Canada, 3.4 million Canadians have diabetes. This number is expected to grow to more than five million by 2025. Considering the prevalence and predicted growth of diabetes, the time for preventive action is now.

WHSC training supports prevention

Specific to this issue, Workers Health & Safety Centre offers hours of work training along with fact sheets exploring the risk to worker health posed by long work hours and shift work. These resources are designed to help workplace parties play a more informed role, seeking prevention solutions around the issue of unhealthy work hours.
Note: WHSC is also in the midst of updating our hour of work training program. Watch for notice of its release some time later this summer.
To learn more:
Call:     1-888-869-7950 and ask to speak to a training services representative.