From Harvard School of Public Health (HSPH) Press Release Previous studies focused on the association between shift work and increased risks of cancers and cardiovascular disease. The HSPH study is the largest study to date exploring the link between shift work and type 2 diabetes. It’s also the first large study to focus on women.
The results: Women working a rotating (irregular) schedule with three or more night shifts per month, in addition to evening and day hours, may have an increased risk of developing type 2 diabetes compared to women who work only days or evenings.
Researchers at HSPH studied data on more than 69,269 US women, ages 42 to 67, in the Nurses’ Health Study I, followed from 1988 to 2008, and 107, 915 women, ages 25 to 42, in the Nurses’ Health Study II, followed from1989 to 2007.
Researchers found the longer the women worked rotating night shifts, the greater their risk of developing type 2 diabetes. Women who worked rotating night shifts for 3 to 9 years faced a 20% risk of developing the disease; those who worked nights for 10 to 19 years had a 40% risk; and women who worked night shifts for over 20 years were 58% more at risk.
Also, women on the rotating night shifts gained more weight and were more likely to become obese during the follow-up.
Because 96% of the participants were white Caucasians, the findings need to be confirmed in men and some ethnic groups. Additionally, further studies are needed to identify underlying mechanisms for the association because of the large number of workers on rotating shifts.
The results are of considerable public health significance. According to the US Centers for Disease Control and Prevention, about 15,000,000 Americans work full time on evening, night and rotating shifts.
Senior author of the study, Professor Frank Hu, says, “This study raises the awareness of increased obesity and diabetes risk among night shift workers and underscores the importance of improving diet and lifestyle for primary prevention of type 2 diabetes in this high risk group.”
My Take on the study: Diet and lifestyle. It comes down to two areas in our lives that we can control to protect ourselves from type 2 diabetes.
But not easy.
TYPE 2 DIABETES: To stay abreast of Lake County Battles Obesity, visit Ron Graham’s blog for the Lake County General Health District at http://lcghd.blogspot.com Visit often. The life and limb you save may be your own.