For many of us, the onset of fall and winter is a difficult time. We stay home and see fewer people, and wake up and go to bed in darkness. It’s not surprising that 20% of the Canadian population has symptoms of the “winter blues.”
Seasonal affective disorder or SAD (sometimes more casually referred to as “seasonal depression”) is a more severe form of this. People living with this type of depression make up 2–3% of the population and experience significant suffering that can prevent them from functioning at their normal level.
how can you recognize the symptoms of seasonal depression?
When you live with seasonal depression, you may experience some of the following symptoms:
- Depressive mood almost all day, almost every day
- Decreased interest and enjoyment in the activities you usually enjoy
- Increased appetite
- Longer sleep, difficulty getting out of bed in the morning and lower energy
- Decreased concentration or ability to think, or indecision
- Feeling slow, or, conversely, agitated
- Feeling guilty or worthless or even, in some cases, having thoughts of death or suicide
People with SAD have two very common symptoms: increased appetite—especially for carb-rich and sugary foods—and longer sleep (hypersomnia).
Several symptoms of SAD are similar to those of major depression, but there’s one specific thing that tells them apart: the timing and recurrence of these symptoms.
If you’ve been experiencing depressive symptoms every year for two years or more, and they recur at the beginning of fall or winter and persist until spring, you may be living with SAD. In some very rare cases, it can also occur in the summer.
shedding light on the causes of seasonal depression
Although the symptoms of seasonal affective disorder are undebatable, the research community is far from agreeing on the causes of this type of depression.
Some go so far as to challenge the very existence of SAD, pointing out that depression is multifactorial in origin and asserting that factors other than the season should be taken into account in diagnosis and treatment.
This being said, SAD is officially recognized by the Diagnostic and Statistical Manual of Mental Disorders (DSM) under the name “depressive disorder with seasonal pattern.”
The most frequently cited cause is a lack of sunlight during the onset of autumn and winter—
not to mention the time change that shortens the period of daylight during the day. One study even found an increase in the number of depressions following the switch to winter time.
This decrease in daylight results in:
- A drop in serotonin(the happiness hormone), which affects our mood
- An increase in melatonin (the sleep hormone), which makes us want to sleep
- A disruption in circadian rhythms, which in turn disrupts our internal clock
The research community is still trying to understand the factors that might explain why some people need more daylight than others in order to function normally.
Women, for example, are two to nine times more affected by SAD than men are. Young adults are also at higher risk than people over the age of 60.
While it can be difficult to act on the internal factors that might explain seasonal depression (genes, heredity, etc.), you have some power over at least one external factor—lack of light.
light therapy: and then there was light?
Getting outdoors, taking walks and soaking in plenty of natural light are just a few of the many ways you can prevent or alleviate SAD symptoms.
When the condition requires treatment, the general recommendation is light therapy, unless contraindicated or in the event of side effects (headache, nausea, or eye fatigue).
This is first-line treatment for seasonal depression, just like antidepressants, for the simple reason that its effectiveness has been demonstrated. The success rate is around 60 to 90%. (And no, tanning salons don’t have the same effect, because light therapy acts on the retina!)
This means your eyes need to be open and about 30 to 50 cm away from your lamp during a light therapy session. To prevent irritation to your eyes, it’s best not to look at the light directly. Instead, keep the lamp next to you while you have your lunch, for example.
The recommendation is to expose yourself to a lamp with a power of 10,000 lux for 15 minutes a day, ideally upon waking. You can find out your own circadian cycle with this online tool.
For more severe forms of SAD, light therapy is usually combined with antidepressant prescriptions, consultations with a psychologist, or other forms of mental health support.
We have all been there, sometimes, finding energy and hope to keep moving forward can be difficult. At Relief, this is something we are all familiar with, that is why our mission is to guide you to better understand your path to mental health.
Discover how to live with seasonal depression
Relief would like to thank Charles Saliba-Couture for his contribution to this article.