a seasonal tendency to depression or SAD ( seasonal affective disorder ) is a variant of the classic depression. The patient has mostly the same symptoms, but they then go with the seasons. seasonal depression peaks are in the fall and winter, where the famous “winter depression.””It’s very common,” said Filip Raes, professor in the psychology of learning center and experimental psychopathology KU Leuven, interviewed by de Morgen. “According to studies, 1-3% of people suffer from winter depression.”

Stability despite the seasons

But the new study, published in the journal Clinical Psychological Science by Auburn University, wonders whether the SAD must be considered as a separate embodiment. The study was done on a large scale, it is interesting to observe the results. Nearly 35,000 subjects between 18 and 99 years, and distributed in the United States took part. The study considers the questions about their symptoms, but also the season in which they were interrogated, where they live and their exposure to daylight.

Result: no matter where they are located, the season or the rate of exposure to daylight, the frequency of depression remains relatively stable. “The study shows that there is little evidence that depression reached a peak in winter,” says Professor Raes. “The authors argue that the seasonal trend vacuum can not exist. And if there were, the cases would be very rare.”

How is winter depression thus appeared in textbooks? The first studies on the subject date back to 80. We then asked the subjects if their depressions occurred mostly or to a specific period. “The memory can be distorted, and people can quickly conclude that their symptoms occur mainly during the winter,” says Filip Raes. The study by Auburn University is not the first to question the very existence of winter depression. But this is the first that is done on such a large scale and which is also credible.

Light Therapy

“To say that depression is caused by a lack of sunlight may be incorrect,” says Raes. “The weather and light levels may have a modest impact on a person’s mood, as several studies. But to say that this has a cause and effect with a disorder such as depression, it seems less likely. ”

The new study does not prove as far as light has no role to play with regard to depression. Light therapy is the proof. “Light therapy seems to be very effective, but also works for depression that had nothing to do with the season” or sunshine. The absence of light is not a cause in itself, but rather the solution. To better understand, Filip Raes compares “The aspirin are effective against headache, but that does not mean that headaches are caused from a lack of aspirin”