Everything You Need To Know About Seasonal Affective Disorder

Every year, around the chilly, grey days of February, Erin Michalak doesn’t feel quite herself. “My mood and energy levels are lower, I'm more fatigued, more easily overwhelmed, less productive and anxious about things I would normally take in stride,” says the UBC psychiatry professor, who specializes in mood and anxiety disorders.

Michalak says the changes are due to mild seasonal affective disorder, also known as “the winter blues.” While the “winter blues” is typically used to describe mood shifts that are not severe enough to be diagnosed as depression, seasonal affective disorder (SAD) is a form of clinical depression that follows a seasonal pattern. With the added stressors of the pandemic, Michalak notes that Canadians need to be extra vigilant about SAD.

“Personally, I know that my resiliency is down and what might be a mild form of depression for me could have the potential to be something that I struggle with a lot more this year,” says Michalak, who has research expertise in SAD.

Deanne Simms, clinical director of the Canadian Mental Health Association (CMHA) York and South Simcoe, is already seeing heightened concern about SAD from patients.

“It’s estimated that SAD makes up 10 percent of reported cases of depression and approximately 15 percent of Canadians will report at least a mild case of SAD in their lifetime—and then there’s about two to three per cent that will report a serious case,” says Simms.

Here is what mental health experts want Canadians to know about SAD, its symptoms and treatments options.

What is seasonal affective disorder?

Research indicates that SAD is linked to decreasing exposure to sunlight in the fall and winter. Put simply, Simms explains: “When we get less light, it impacts the chemicals in our brain which are important for sleep and mood.”

As a result, around November, when the days get shorter and we retreat indoors for the winter, people can become irritable, lethargic, fatigued and unmotivated and experience an increased appetite—particularly a craving for carbs, which some research links with an increase in serotonin (i.e. eating carbs makes us feel good)—and weight gain.

These symptoms may persist for months, peaking around January or February, and then typically improving around the arrival of spring around March. SAD is also much more commonly seen among women, though researchers haven’t pinpointed exactly why.

Since SAD is connected to light exposure, risk varies based on location. “Vancouver and Toronto are known to be bad cities in Canada for SAD because they tend to be grey during the wintertime, whereas in the prairies it’s often very cold and bright and that brightness, especially if there’s lots of snow, can actually be quite good for SAD,” explains psychiatrist Dr. Robert Levitan, who has published multiple studies on the disorder.

Levitan, who holds the Cameron Holcombe Wilson Chair in Depression Studies at CAMH and University of Toronto, adds that Vancouver and Toronto have also experienced tighter pandemic restrictions, which may contribute to the number of people experiencing SAD in those cities this year.

What are the potential signs of SAD?

It’s easy these days to feel more sluggish than usual. So how can you keep an eye out for symptoms of SAD?

“Whenever we think about any of these symptoms, we think about a change from a person’s baseline,” explains Simms. For instance, someone who typically sleeps 7 hours per night suddenly sleeping 10 hours, napping throughout the day and still feeling tired.

To get a sense of that baseline, and potential fluctuations, Michalak highly recommends using a mood tracker. There are apps and journals to help record your feelings over time, but Michalak says it can be as simple as writing down your daily mood on a 10-point scale. Not only can this data help reveal problematic patterns, it is also great information to share with your healthcare provider.

How can you fight SAD?

Maintaining a healthy lifestyle, with regular exercise, healthy eating habits and social interaction can all help combat the onset of SAD. But Simms also points out that pandemic restrictions may impact your ability to do some of those activities.

Her advice? “Control the controllable and do the doable.” For instance, if you're hesitant about going to the gym, work out at home. Invest in warm winter gear and make sure to get out each day. Stay connected to friends. Sticking to a regular routine, that includes a set wake time and bedtime, can also help.

“We’ve got to get creative,” says Simms, who admittedly doesn’t love the cold, but is determined to try new outdoor activities this year. “We need to rethink what Canadian winter looks like.”

Do SAD lamps really work?

Light therapy, meaning the use of a bright artificial light, is the go-to treatment for SAD. Research has shown that SAD lamps—that is, a lamp or light box that mimics sunlight—can help activate the parts of the brain that are responsive to sunlight, thereby combating the effects of SAD.

It’s important to note that SAD lamps are specialty devices that differ from everyday household lighting. For those purchasing a SAD lamp, Levitan emphasizes the need to make sure the light is ultraviolet filtered. The standard recommendation is to look for a SAD lamp that shines at 10,000 lux and use it for 30 minutes each day (alternatively, a 5,000 lux lamp can be used for one hour each day), preferably early in the morning.

“Try not to sit and stare into this lamp because the light can damage your eyes,” cautions Simms. SAD lamps should be placed 16 to 24 inches away from your face, she explains, and the light is meant to enter your eyes indirectly, such as if it is placed next to you while reading or working on the computer.

While these devices can be purchased online, or even used at many Canadian libraries, experts warn that Canadians should only explore this option with the help and guidance of a healthcare professional.

Consult a healthcare professional

Whether you’ve experienced SAD in previous years, or noticing signs and symptoms for the first time, healthcare providers can help.

“One of the other ways to intervene is through psychotherapy or psychological help,” says Simms. “So we know that cognitive behavioural therapy can help people manage their thoughts, moods and feelings and can also help target different lifestyle changes in the winter.”

Many people experience mild symptoms of SAD, but certain behaviours may indicate that it’s time to consult a family doctor or therapist.

“If you can’t function at work because your mind is cloudy all the time or if you can’t function in a relationship at home because you’re sleeping all the time, or irritable or apathetic. If it’s starting to affect your day-to-day life more days than not, that’s when we call it clinical depression,” says Levitan. In particular, if there are thoughts of self-harm or suicide, people should seek professional help immediately.

“Depression is a trickster. It slips up on you,” says Michalak, who plans to start regular light therapy in January and step up her exercise and self-care routine this winter. She encourages Canadians to be vigilant about their moods and take positive steps to protect their mental health, especially during the pandemic. “Arming yourself with that information and being a bit more proactive this year is going to be [even] more important.”

This article was originally published in 2020; updated in 2021.