The winter months leave Canadians with less sunlight and cause some to experience a change in mood.

Seasonal Affective Disorder (SAD) is a term which encompasses many of the symptoms of the winter blues.

"More specifically, SAD is a condition that we talk about at this time of year that is a subset of depressive disorder," said Dawn Sawatsky, Mental Health Liaison Nurse for Southern Health-Santé Sud.

Common symptoms of SAD include a reduced interest in usual activities or decreased concentration. "Low energy, fatigue, just feeling drowsy throughout the day," said Sawatsky.

Sawatsky noted that serotonin, melatonin and your circadian rhythm all play a part in the change of season.

Dawn Sawatsky (submitted photo)

"A recent Denmark study suggests, actually, that there is a connection between time change and affect on people's mood, so that is leading right into winter season," Sawatsky said.

"There is a marked increase in the months following Autumn... where there's marked increase in diagnosis of depression," she added.

Sawatsky notes researchers believe SAD can present with varying levels of severity.

"Typically about 5 per cent of the population will get SAD," she said. "Typically in areas that are further away from the equator, those are the populations that are seemingly getting higher levels of SAD."

This is because less access and exposure to sunlight during the winter months results in decreased production of serotonin.

"When light enters our eyes, it produces serotonin," said Sawatsky. "Apparently that does have an affect on our mood."

When it comes to being proactive and battling symptoms, healthy sleeping and eating patterns can play a role.

Research out of Ryerson University suggests resisting the urge to sleep longer than recommended, said Sawatsky.

"We don't want to over sleep or under sleep, essentially," she said.

Other suggestions for a good quality sleep include winding down before bed, turning off screens, clearing your thoughts, and having healthy nutrition habits.

Light therapy can also be helpful, although is not meant to replace sunlight, said Sawatsky. SAD Light rental or purchases are available through the Mood Disorders Association of Manitoba.

Sawatsky notes a marked change in appetite, activity, and loss of interest can be a sign of a major depressive disorder. Help from a doctor should be sought if symptoms interfere with every day life, or include feelings of worthlessness or thoughts of self-harm.

Another available resource is the Crisis Response Service at 1-866-588-1697 or 1-888-617-7715 for residents east of the Red River.