Employees working varied hours over a shift pattern run a higher risk of developing diabetes, according to experts.
Medics, police officers and fire fighters are among workers who are 9% more likely to develop diabetes, a study published in the journal Occupational and Environmental Medicine said.
Men working working on a shift pattern emerged as the most at risk candidates for developing diabetes - their chances rose by 37%.
Previous research has linked shift work to weight gain and increased appetite - both of which are risk factors for diabetes, the authors said.
Researchers examined 12 studies involving more than 225,000 people, of whom almost 15,000 had diabetes.