There are some who don't need an excuse to skip a day's work - but this could be a good reason to quit your job altogether.
A badly-paid or temporary job can be as bad for a person's mental health as none at all, researchers claim.
Little job security, demanding work and poor managers can all impact on a person's well-being just as much as unemployment
A University of Lancashire study, which included in-depth interviews with 24 men and women in management and non-management positions in a variety of job sectors, found anger is widespread at work. It most often erupts over immoral behavior (cheating, lying, stealing) or when people feel they've been unfairly treated (unjust criticism or heavy workload).
Other common triggers of workplace anger include incompetence, disrespect, failure to communicate or exclusion.
In fact, people who are unemployed can feel better-off mentally than those who are in poor jobs of low 'psychosocial quality', the report added.
Researchers said government policies tend to focus on job seekers when they should also take into account the quality of a person's job.
Writing in the journal Occupational and Environmental Medicine, a team at the Australian National University in Canberra, said: 'This study has shown that work of poor psychosocial quality, characterised by low job control, high job demands and complexity, job insecurity and the perception of unfair pay, does not bestow the same mental health benefits as employment in jobs with high psychosocial quality.
'In fact, we found that moving from unemployment to a job with poor psychosocial quality was associated with a significant decline in mental health relative to remaining unemployed.
'This suggests that psychosocial job quality is a pivotal factor that needs to be considered in the design and delivery of employment and welfare policy.'
Studies have long found that people in work enjoy better mental health than those who are unemployed.
But fewer studies have examined how people feel about their jobs when they are in employment.
Researchers analysed data from more than 7,000 people in Australia and found well-being was very much dependent on the quality of the job.
The scientists found moving from unemployment into a high-quality job led to improved mental health but moving from unemployment to a poor-quality job was more detrimental than remaining unemployed.
Experts found a direct association between the number of unfavourable working conditions and mental health.
As the quality of a job deteriorated, a person became more likely to experience poor mental health.
Managers are especially important to employee well-being, says Robert Hogan, from the University of Tulsa.
'Bad bosses will make anybody unhappy,' Professor Hogan told Health Magazine. 'Stress comes from bad managers.'