Overdoing it at work is bound to make you tired, grumpy and stressed.
But research suggests it could also significantly increase your risk of developing type 2 diabetes - even if you're not overweight.
A major study has found that those under the most strain at work are 45 percent more likely to fall ill with the condition, which increases the risk of heart disease, strokes, blindness and amputations.
The study, from the Institute of Epidemiology in Munich, followed 5,337 men and women aged between 29 and 66 who were in full-time work.
Over a 12-year period, nearly 300 of the subjects - who were previously healthy - developed type 2 diabetes.
As well as measuring body mass index (BMI) and family medical history, researchers quizzed volunteers on their stress levels at work. High job strain was defined as being faced with huge demands but having little control over how things are done.
When the researchers matched patients with the work stress results, they found those who were under most pressure were 45 percent more likely to have developed diabetes.
The findings - published by journal Psychosomatic Medicine - showed that even among workers with relatively healthy BMIs, stress at work was still a significant risk factor.
A high BMI of 30 or more is usually seen as the diabetes danger zone.
Researcher Professor Karl-Heinz Ladwig said: 'According to our data, roughly one in five people in employment is affected by high levels of stress at work.
'We don't mean normal job stress but rather the situation in which the individuals concerned rate the demands made upon them as very high and at the same time have little scope for maneuver or decision-making.'