Dolly Parton once sang that working 9-5 is “all taking and no giving,” but working outside of these hours may take away much more – when it comes to our health, at least. A new study finds people who work shifts are more likely to have sleep problems than people who follow conventional work schedules, which may raise their risk of metabolic disorders such as obesity and diabetes.

Share on Pinterest People who work shifts are at higher risk of sleep problems, which may be a driver of metabolic disorders including obesity and diabetes.

Lead investigator Dr. Marjory Givens, an associate scientist at the University of Wisconsin School of Medicine and Public Health in Madison, and colleagues published their findings in Sleep Health – a journal of the National Sleep Foundation.

The link between shift work and poor health is not new. In July 2014, a study linked shift work – particularly rotating shifts – to increased risk of type 2 diabetes, while a more recent study found people who work rotating night shifts for at least 5 years are at higher risk of all-cause and cardiovascular mortality.

Using 2008-12 data from the Survey of the Health Wisconsin (SHOW), Dr. Givens and colleagues set out to investigate the health implications of shift work further – specifically, how shift work affects sleep, weight and diabetes risk.

For SHOW, all participants were subject to home- and clinical-based physical assessments and interviews.

The team analyzed 1,593 participants who underwent a physical examination, using the data to calculate their body mass index (BMI) in order to establish their overweight or obesity status.

The data of a further 1,400 participants with type 2 diabetes was assessed. Their condition was determined by either a self-reported physician diagnosis or by the presence of glycated hemoglobin (HbA1c) in the blood at levels of 6.5% or higher at physical assessment.

The working patterns of participants were recorded during interviews.