Seasonal Affective Disorder or S.A.D has not yet been classified as a distinct psychological disorder.

S.A.D tends to affect most people throughout their life and some of us probably don’t even know it. It seems to be that with the changing of seasons peoples moods will change, depending on the amount of sunlight or rain there is.

The most common times of year for people to slip into a depressive state is winter. The days are shorter and colder, its bleaker and more unpleasant outside. The sufferer becomes a vegetative depressive, not wanting to do anything much at all. The sufferer will tend to eat more and sleep more, experience chronic fatigue and gain weight. In some extreme cases of S.A.D the sufferer can also have significant social withdrawal.
Eventually, with the onset of spring the sufferer comes out of ‘hibernation’ and depending on circumstances improvement is almost immediate.

However in some people the effect of S.A.D. can be quite severe, and bring about symptoms of depression that interfere with normal daily functioning. The good news is that it is usually able to be appropriately treated with very minimal effort or side-affects.

Research is still being carried out in this area of depression to find out if Seasonal Affective Disorder is due to the seasons or if it is a recurrence of major depression or another mood disorder, which is triggered or exaggerated by the changing seasons. There has been some study done using sunlight. Sunlight entering through the retina stimulates the production of chemicals in the brain that appear to have an antidepressant affect, this form of therapy is also known as ‘Bright Light Therapy’ or BLT.

Seasonal Affective Disorder appears more prevalent in people who are younger, live at higher latitudes ie; further North, and in (generally speaking) women.

People who are young: it is unknown yet whether S.A.D affects younger people more often because of a biological pattern, related to age, or if it is just the way that younger people tend to describe the depression that they may suffer from.

People who live at higher latitudes: more Northern countries and states tend to have less sunlight, with harsher winters that produce colder conditions and frequent storms.

People of different genders: women are more likely to be diagnosed with S.A.D than men, the most reasonable answer to this would be that more women are diagnosed with depression than men. Another possible reason for this could be that women with small children tend to be more isolated during the winter months than those women with careers. Men are generally not left at home to look after small children and so it seems that another reason for S.A.D could be that if caretaking was an equally shared job then there may be less women diagnosed with S.A.D.