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. However, these are generalisations - there are plenty of SAD sufferers whose symptoms look like clinical depression rather than SAD and sufferers do commit suicide. As the main cause of SAD is lack of light it stands to reason that the main way of controlling the disorder is by using light treatment, sometimes called phototherapy. There is an ever-growing range of light equipment available. The main ones so far are light boxes, visors and dawn simulators.