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.
The collaborative research team observed 2,000 middle-aged men and women in the United Kingdom for six years. Following a thorough analysis of research data, they reported a strong correlation between length of overtime work and risk of depression. The study included 1,626 males and 497 females with the average age being 47.
The correlation between overtime work and depression risk remained unchanged even when variables were controlled such as different lifestyle choices (alcohol consumption), tension level at work and socioeconomic factors.
Working overtime for long periods of time causes our bodies to release stress hormones called cortisol. Researchers reported that the heightened level of cortisol further leads to the development of a full-blown depressive disorder.
Doctor Marianna Virtanen of the Finnish Institute of Occupational Health views that overtime work can be beneficial to both individuals and society to some extent.
Dr. Virtanen, however, stresses the importance of society acknowledging the harmful effects of overtime work and the associated risk of developing depression. Current research findings were published in "PLoS One," an online journal of the American Public Library of Science.