Whatever the trouble, from disasters like a plane crashes, companies going bust or less acute personal problems like tiredness and a lack of concentration, November is the best month for it, said head of the Kiel Institute for Crisis research Frank Roselieb.

Suicide, he told Die Welt newspaper, was far more common in the darker months of the year than in the summer.

In low light, the human brain produces more melatonin – which makes a person sleepy. This means that they generally have lower concentration levels and are more easily overwhelmed, said Roselieb.

He said when a person has a bad day during the summer, others who are happier tend to cheer them up. “In the winter this support is gone because we’re all having a bad day,” he said.

But all was not lost in the gloomy German winter, as the crisis-expert said that awareness of the winter-blues was increasing and some employers were even offering courses on how to cope.

There were also firms, Roselieb said, which employ more staff in the late autumn, in preparation for the winter and the increased numbers of people off ill or suffering from “winter-blues”.

Scandinavia has long led the way in dealing with short, dark days. In Norway, offices often lengthen their working days in the winter to between nine and ten hours, while their working days in the summer are reduced to between six and seven hours.

“Employers have accepted that people are less productive in the winter and need more time to do their work.”

In Sweden, many offices install special daylight lamps. “Humans can think better, work better and are more alert in a bright office,” said Roselieb.

The Local/jcw