Night shift work has long been associated with a string of health problems such as sleep disorders and an increased risk of obesity, diabetes, and heart disease. In a new study, Harvard School of Public Health researchers quantified just how much rotating shift work contributes to the risk of diabetes -- which occurs in 1 in 12 American adults -- and it’s pretty significant.
The study, involving more than 175,000 nurses, found that those who worked night shifts three or more times a month were more likely to develop type 2 diabetes over 20 years compared with people who didn’t work night shifts. Those who worked night shifts for one to two years had nearly no increased risk, while those who did them for three to nine years had a 20 percent greater risk of diabetes, with risks continuing to rise with more years of night shift work. Those who worked nights for more than 20 years had a nearly 60 percent greater risk of diabetes, according to the research published in the journal PLoS Medicine.