As the days get shorter and darker, about one in 300 Australians will experience SAD signs and symptoms.

Seasonal affective disorder – SAD – most commonly arises in people in the autumn and winter months, and typically in countries in the northern hemisphere that experience particularly long nights and low levels of sunlight.

As Australia approaches the shortest day of the year, June 22, the disorder can start to creep into people’s lives.

It’s not known exactly what triggers SAD, but most medical professionals agree it’s linked to exposure to light, the body clock, and serotonin and melatonin levels. It can affect anyone, but most commonly women and young people.

GP and Beyond Blue lead clinical adviser Grant Blashki said the disorder, which once stood on its own, was now considered a subtype of major depression.

Its typical symptoms are similar to that of depression – feelings of hopelessness and worthlessness, loss of interest in activities, withdrawing from social situations, overeating (especially carbs), over-sleeping, and a lack of energy and motivation.

However, in SAD, these symptoms become more pronounced in the winter months.

“During the winter months, some people might find it hard getting out of bed or getting motivated,” Dr Blashki said.

“The difference is if it’s affecting your day-to-day life.

“If you can’t get along to work, if it’s persistent, and you find you’re not getting much joy out of anything, if you’re very tired – it’s time to see your doctor.”

From there, Dr Blashki told The New Daily, a GP might order a blood test to check your iron levels and thyroid function, and even consider a course of anti-depressant medication.

If warranted, they may refer a patient to a mental health professional.

“The other important thing to note with SAD is that it just keeps coming back every year. If it’s five years in a row, and you think, winter is here, my mood has hit the floor – that’s an indicator,” Dr Blashki added.

The seasons affect the body

When it comes to beating off the blues and staying mentally fit in the colder months, Dr Blashki said there were two key things people could do: Get outside, and get moving.

“The obvious thing is to get more sunlight, if you can,” he said.

“There’s also very good evidence that more exercise helps.”

There’s also light therapy, which is something GPs can provide advice on, and involves – as the name suggests – scheduled exposure to artificial light to boost the mood.

Light therapy can help people suffering from seasonal affective disorder. Photo: Getty

“You use (the light) preferably in the morning for between 20 and 30 minutes. You hold it about 50 centimetres from your face, with your eyes open but not looking at the light,” said Dr Blashki, who has recommended it to his clients, with successful results.

He said it was important to consult a GP about using light therapy before diving in, due to specifications and pre-existing conditions that might affect its efficacy.

Switch off

Other professionals have also suggested decreasing social media use to keep mood levels up.

Because we’re more likely to spend more time inside in cold weather, we’re more likely to be scrolling through various platforms. And that’s not necessarily a good thing.

“A number of studies have shown that the more people scroll through happy status updates, holiday snaps and such, the worse they feel,” Brad Ridout from University of Sydney’s Cyberpsychology Research Group told the ABC.

“This is because while most people consciously know that people tend to post a carefully chosen highlights reel of their life on social media, it still hits us on an emotional level and leaves us feeling like everyone else is living more exciting lives than us.”

The tip? Reduce your social use, or unfollow/hide anyone on a winter vacation in the tropics.