The impact on mental health of a badly paid, poorly supported, or short term job can be as harmful as no job at all, indicates research published online in Occupational and Environmental Medicine.
Because being in work is associated with better mental health than unemployment, government policies have tended to focus on the risks posed by joblessness, without necessarily considering the impact the quality of a job may have, say the authors.
They base their findings on seven waves of data from more than 7000 people of working age, drawn from a representative national household survey conducted every year in Australia (HILDA).
Respondents' mental health was assessed using a validated inventory (MHI). And they were asked about their employment status.
If in work, the "psychosocial" quality of their job was graded according to measures relating to demands and complexity; level of control; and perceived job security. Respondents were also asked if they felt they received a fair wage for the work they did.
Not unexpectedly, those who were unemployed had poorer mental health, overall, than those in work, the results showed.
There is some evidence to show that employment is associated with better physical and mental health, and the mental health of those out of work tends to improve when they find a job, say the authors.
But after taking account of a range of factors with the potential to influence the results, such as educational attainment and marital status, the mental health of those who were jobless was comparable to, or often better than, that of people in work, but in poor quality jobs.
Those in the poorest quality jobs experienced the sharpest decline in mental health over time. There was a direct linear association between the number of unfavourable working conditions experienced and mental health, with each additional adverse condition lowering the mental health score.
And the health benefits of finding a job after a period of worklessness depended on the quality of the post, the findings showed. Job quality predicted mental health.
Getting a high quality job after being unemployed improved mental health by an average of 3 points, but getting a poor quality job was more detrimental to mental health than remaining unemployed, showing up as a loss of 5.6 points.
Paid work confers several benefits, including a defined social role and purpose, friendships, and structured time. But jobs which afford little control, are very demanding, and provide little support and reward, are not good for health, say the authors.
"Work first policies are based on the notion that any job is better than none as work promotes economic as well as personal wellbeing," comment the authors. "Psychosocial job quality is a pivotal factor that needs to be considered in the design and delivery of employment and welfare policy," they conclude.
Explore further: Schizophrenia, bipolar disorder associated with dendritic spine loss in brain