Aug 1, 2007
A study of 1,000 32-year-olds found 45% of new cases of depression and anxiety were attributable to stressful work.
They defined a highly demanding job as involving a lack of control, long hours, non-negotiable deadlines, and a high volume of work.
Experts said the paper in Psychological Medicine showed employers needed to do more to protect workers' mental health.
Researchers looked at people who had taken part in a major, long-term study being carried out in Dunedin, New Zealand, to follow their progress through life.
They had a wide range of jobs including actress, brain surgeon, teacher, helicopter pilot, dustbin man, journalist and policeman.
They were asked whether they had workload and time pressures, had to work longer hours than they would like, had too much work to do everything well, whether their job was hectic, were often unclear about what they had to do and have to work too hard.
Overall 10% of men and 14% of women in the study suffered a first episode of depression or anxiety over the year-long study.
But the risk was double in those with the highest pressure jobs.
Study leader Dr Maria Melchior, epidemiologist at the Institute of Psychiatry, Kings College London, said: "Our study shows that work stress appears to bring on diagnosable forms of depression and anxiety in previously healthy young workers."
She added that those taking part in the study were at an age where they were settling into their careers and are less likely to have opted out of less stressful jobs.
"There are a number of possible mechanisms - previous research suggests there could be an effect on stress hormones in the brain which could lead to depression, also fatigue and lack of sleep."
People in high-pressure jobs may also have less time to take part in social activities, she added.
Co-author, Professor Terrie Moffitt, also at Kings College London added that jobs where failure was highly visible, such as working as a head chef in a busy restaurant, were among the most demanding.
"At the other end of the spectrum people who work in home child care looking after two or three children would have a more predictable daily life."
Professor Cary Cooper, professor of organisational psychology and health at the University of Lancaster said jobs were becoming increasingly pressured.
"We have got to get people to work much more flexibly, using technology to our advantage rather than keeping people in an office environment for long hours.
"Also we need to get managers to behave differently - manage by praise and reward rather than by punishment and understand that people need to feel they have control over their work."