Mental health in winter: Why you may have been feeling sad yesterday

The symptoms of SAD can develop over a period of weeks or months and can lead to change in routine, sleep patterns and eating habits. Photo / 123RF

Yesterday was the shortest day of the year in the Southern Hemisphere – and with fewer daylight hours linked to feelings of tiredness, sadness and less interest in social activities, if you were feeling a bit down yesterday, you weren't alone.

The Winter Solstice brings with it just nine hours and 54 minutes of daylight and the longest night of the year and is associated with a form of depression known as Seasonal Affective Disorder, or SAD.

The cooler months are a common trigger for SAD, with symptoms often appearing in autumn and winter and fading away around spring and summer.

SAD is believed to be triggered by changes to the body clock at certain times of the year and due to the body producing less of the mood-boosting hormones melatonin and serotonin during the winter months.

Often dismissed as the winter blues, the condition should be taken seriously, says Macquarie University Professor of Psychology Nick Titov.

"People aren't exactly sure how it comes about. I think the reality is about 5 per cent of the Australian population every year will have clinical depression or major depressive disorder and a proportion of those people will have Seasonal Affective Disorder," Professor Titov said.

"We all know in winter we tend to change our habits and our routines, we tend to do less, we in some respects all like to hibernate to some degree or other but it's believed there are a number of hormones or neurotransmitters which are affected by changes in light, which for some people who are vulnerable, can lead to Seasonal Affective Disorder."

The symptoms of SAD can develop over a period of weeks or months and can lead to change in routine, sleep patterns and eating habits.

"There are some very profound symptoms. People often feel sad. They lack energy. They lose interest in the usual activities and things they enjoy and used to give them pleasure," Professor Titov said.

"But they also have changes in their sleep patterns and their appetite. They eat more and almost crave more high-carbohydrate or high-calorie foods and invariably they feel hopeless about themselves, the world and the future.

"For people who experience winter blues, and many people experience winter blues, then there are lots of things we can do to improve our mood.

"If it's proper Seasonal Affective Disorder, it is a serious condition and we would strongly encourage people to reach out.

"There's a number of different psychiatric and psychological approaches. There are medications that are helpful, antidepressant medication.

"It depends really on the individual. Some people respond really well to techniques such as cognitive behavioural therapy, whereas other people do respond very well to medication."

Professor Titov said being aware of changes to your mood or routine could indicate you were affected by SAD.

"There are a couple of things I'd encourage people to do. Firstly, just recognise it's another season. And it's a wonderful, beautiful season," he said.

"Look at what your usual habits and routines are, the things that you normally enjoy and what you may have to change or may have to adapt to ensure you're still getting the stimulation, the satisfaction and the fun in your everyday life.

"Rather than going out necessarily, inviting people around or going to visit with other people, watching movies, enjoying hobbies – so actually schedule activities that are fun and you can look forward to.

"Be mindful about your sleep habits, your nutrition habits – all the things which you know can affect your wellbeing."

If you notice your symptoms linger and begin to affect your everyday life, it's important to seek help from your doctor.

Treatments can include counselling, medication or vitamin B supplements.