A six-year study conducted by the Finnish Institute of Occupational Health and London University suggested that long hours of overtime work not only causes our bodies to become tired but also can cause depression.
The findings showed that those who work more than 11 hours are 2 1/2 times more susceptible to displaying symptoms of severe depression compared to those who work 7 to 8 hours a day.
Read more: http://www.thejakartapost.com/life/2017/11/10/overtime-work-can-cause-severe-depression-study.html