Looking for a reason to change careers? Here's a good one: Hating your job is linked to health problems, even for people as young as 40.

That's according to a new study due to be presented Monday at the annual meeting of the American Sociological Association.

Researchers showed that Americans who spend the early parts of their careers unhappy tend to develop more health problems than those who spend the early parts of their careers satisfied.

Ohio State sociologists examined data about 6,432 participants in the National Longitudinal Survey of Youth (NLYS), which tracks outcomes for people who were between 14 and 22 when it began in 1979.

The NLYS asks its participants to regularly rate their job satisfaction on a scale of one to four. The researchers used those ratings to divide the participants into four groups in terms of the satisfaction they reported between ages 25 and 39:

People who started their career happy with their job and stayed happy (15%)

People who started unhappy but grew happier (17%)

People who started unhappy and stayed unhappy (45%)

People who started happy enough but grew less happy as time went on (23%)

Compared to the sadly small number of folks who enjoyed their entire early careers, those in the largest, unhappiest group were more likely to experience depression, sleep problems, "excessive worry," emotional problems, and lower overall mental health. They also reported more back pain and frequent colds than the happy cohort — though their rate of doctor-diagnosed illnesses like cancer was not higher.

People whose satisfaction trended downward had similar sleep and worry problems, as well as lower overall mental health. They didn't see the same impact of depression and emotional problems though.

The real takeaway here is what happened to folks whose satisfaction trended upward, even if they started out unhappy. That group had no measurable harm at all. The way to beat the mental and physical ravages of hating your job, it seems, is to make moves to put yourself in a more personally satisfying position.

Of course, the big caveat here is that this study didn't prove cause, just an association. Another interpretation of the same data might be that people who experience mental health problems are more likely to report dissatisfaction with their jobs. In all likelihood, there are effects going both ways.

But no matter what, this is research worth keeping in mind as you contemplate the next move in your career.