Long hours in a low-status job can increase diabetes risk by almost a third, research has shown.
People in low-status, poorly paid jobs who work 55 hours or more a week are 30% more likely to develop type 2 diabetes than those putting in 35 to 40 hours, scientists found.
The difference remained after taking account of factors such as smoking, physical activity, age, gender and obesity.
“Work factors affecting health behaviours and stress may need to be addressed as part of diabetes prevention”
Even excluding the impact of shift work, which has been shown to increase the risk of obesity and diabetes, did not alter the result.
Researchers analysed data from more than 222,000 men and women who participated in diabetes studies in the US, Europe, Japan and Australia.
Lead scientist Professor Mika Kivimaki, from University College London, said: “The pooling of all available studies on this topic allowed us to investigate the association between working hours and diabetes risk with greater precision than has been previously possible.
“Although working long hours is unlikely to increase diabetes risk in everyone, health professionals should be aware that it is associated with a significantly increased risk in people doing low socio-economic status jobs.”
“Having diabetes increases someone’s risk of having a heart attack or stroke so reducing that risk is essential”
In an accompanying comment article, Dr Orfeu Buxton, from Pennsylvania State University, and Dr Cassandra Okechukwu, from Harvard School of Public Health, wrote: “The results remained robust even after controlling for obesity and physical activity, which are often the focus of diabetes risk prevention, suggesting that work factors affecting health behaviours and stress may need to be addressed as part of diabetes prevention.”
Maureen Talbot, senior cardiac nurse at the British Heart Foundation, which co-funded the research, said: “The findings of this study suggest a link between working more than 55 hours a week and an increased risk of developing Type 2 diabetes, but only in those people deemed to be in low socio-economic groups.
“The study’s authors confirm more research into this finding is needed,” she said. “Having diabetes increases someone’s risk of having a heart attack or stroke so reducing that risk is essential.”