Make a note to switch your clocks on Sunday, November 6 — the day we change from daylight savings time to standard time. But also keep an eye on your mood since the transition can lead to depression.

According to Danish poet Henrik Nordbrandt: "The year has 16 months: November, December, January, February, March, April, May, June, July, August, September, October, November, November, November, November. "

A new Danish study found that people diagnosed with depression in Danish hospitals increased immediately after the time change.

The study is based on analysis of 185,419 depression diagnoses registered in The Central Psychiatric Research Register between 1995 and 2012.

According to Søren D. Østergaard from Aarhus University Hospital in Risskov, the 8 percent increase in depression is too significant to be coincidental.

"We are relatively certain that it is the transition from daylight saving time to standard time that causes the increase in the number of depression diagnoses and not, for example, the change in the length of the day or bad weather," he said. "In fact, we take these phenomena into account in our analyses."

Østergaard also points out that even though the study is based on analysis of relatively severe depressions diagnosed at psychiatric hospitals, there is no reason to believe that the time transition doesn't also affect less severe types of depression.

"We expect that the entire spectrum of severity is affected by the transition from daylight saving time to standard time, and since depression is a highly prevalent illness, an increase of eight per cent corresponds to many cases," says Østergaard.

The study does not identify exactly what triggers the increase, but researchers speculate it may be due to "moving" an hour of daylight from the afternoon to the morning.

"We probably benefit less from the daylight in the morning between seven and eight, because many of us are either in the shower, eating breakfast or sitting in a car or bus on the way to work or school. When we get home and have spare time in the afternoon, it is already dark," explains Østergaard.

"Furthermore, the transition to standard time is likely to be associated with a negative psychological effect as it very clearly marks the coming of a period of long, dark and cold days," he said.

Below are three ways you can fight the depression caused by less light:

Take extra vitamin D. The body makes vitamin D, which has been linked to mood, when the skin is exposed to sunshine, but levels fall even lower as fall and winter approach.

Get more light. Although any amount of outdoor light can help, getting light in the morning seems to offer the most benefit.

Increase exercise. Studies have shown that increasing exercise can help fight depression.