Thirdly, stress seems to be a major trigger. Many sufferers have found that SAD first developed after a stressful life crises such as divorce, redundancy, bereavement or even a new baby in winter. Someone who has previously shown only very mild symptoms may develop severe symptoms if put under stress. But as I have explained above, we all have an internal body clock and SAD appears to be a disorder of that body clock. Hence, it is a bodily illness.
People suffering from clinical depression tend to have difficulties eating and sleeping.
Their symptoms show no seasonal pattern. They tend to prefer the dark. The typical symptoms of SAD are the opposite of the above. Sufferers have a seasonal pattern and eat and sleep a lot. There is a comparatively low suicide and work absentee rate amongst SAD sufferers.