When the colder season comes around and the sun is out less often, you may notice yourself feeling more down than usual. This is pretty normal and commonly known as the "winter blues." But what if your low mood becomes hard to manage and starts impacting your life in negative ways? You might be experiencing seasonal affective disorder (SAD).
What is seasonal affective disorder?
What are the symptoms of seasonal affective disorder?
What causes seasonal affective disorder?
What are some treatments for seasonal affective disorder?
Seasonal Affective Disorder: Definition
Seasonal affective disorder (SAD): a specific type of depression that develops during a specific season (i.e., winter) and resolves once that season is over. It is not its own separate disorder.
SAD impacts over three million people in the US alone! Just like other types of depression, SAD causes emotional and mental distress. From late fall through the end of winter, the change in clock time and season means that there is less sunlight during the day. Even when the sun is out, it is often covered with clouds or gray skies.
Many people experience the "winter blues" in the colder season, Pexels.
If people are from a warm state and go off to college in a cold state, they may be experiencing their first winter. For some, the winter will be cold and different, but that's all. However, for others, the switch in climates and experiencing their first changing of seasons could lead them to SAD.
The most common kind of SAD happens during the winter, but there are some people who experience spring and summer seasonal depression. The summer version of SAD often includes insomnia, weight loss, and aggression. These symptoms are a bit different fro the typical SAD symptoms experienced in the winter.
Seasonal Affective Disorder: Symptoms
Symptoms of SAD are the same as other kinds of depression. Remember, SAD is a type of depression and not its own separate disorder. A diagnosis of SAD means that the person is experiencing depressive episodes in a consistent seasonal pattern.
Seasonal Affective Disorder Symptoms include:
Low mood most of the time.
Loss of interest in activities most of the time.
Low energy levels.
Easily irritated.
Suicidal thoughts and ideation.
Difficulty concentrating or remembering things.
Weight gain or loss.
Sleep issues (sleeping too much or too little).
Increased isolation from others.
Maria is generally a happy person most of the time. However, once the colder months come around and the weather becomes grey and foggy, Maria starts to feel like a completely different person. She becomes increasingly tired and irritable. She no longer enjoys spending time with her friends and prefers to stay at home alone. Above all, she feels very depressed and down most of the time. Once the seasons change again, she gradually returns to her usual bubbly personality. This has been going on for years. Maria may be struggling with seasonal affective disorder.
These symptoms, while similar to those of Major Depressive Disorder and persistent Depressive Disorder, happen at the same time as a change in the climate. If you are experiencing periods of depression, keep an eye out for what time of year they happen.
Seasonal Affective Disorder: Causes
Research is still being conducted to understand the main causes of SAD, but there are many theories about potential causes. Researchers have discovered a few differences in the brains of those with SAD, who have been found to have increased melatonin, decreased serotonin, and decreased vitamin D compared to those without SAD.
Increased Melatonin Production
Have you or someone you know ever taken melatonin to try to help them sleep? It's a little pill that's said to help you sleep better if you take it because melatonin is the hormone responsible for inducing sleep.
Many studies report an increase in the levels of melatonin in people diagnosed with SAD. When there is too much melatonin in the brain, the person will feel increased sleepiness or drowsiness. Interestingly, sunlight exposure is linked to melatonin production (we'll talk about that soon). Lower levels of sunlight signal the brain that it needs to make more melatonin.
When people are experiencing symptoms of depression, they may not go outside as much. Because of this, someone with SAD would be getting less sunlight and, therefore, their body would be telling them to fire up the melatonin factories. This is one reason why those with SAD may be much sleepier than normal.
Decreased Levels of Serotonin
Serotonin, a neurotransmitter in the brain that helps with mood regulation, has also been named a cause of SAD. People with SAD will have low levels of serotonin during the winter months. As with Major Depressive Disorder, serotonin levels are a potential cause of someone developing SAD. The decrease in serotonin makes people more vulnerable to developing depression.
Vitamin D Deficiency
The feeling of sunlight on your skin doesn't just give you a good tan. It is also responsible for the absorption and production of vitamin D in the body. Additionally, there is an association between serotonin and vitamin D. This association then causes there to be a link between low levels of vitamin D and major Depressive Disorder and SAD. Since there is less sunlight in the winter, this can lead to a deficiency in the body and, for some people, SAD.
One study measured the difference between workers who lived close to the equator and who lived the farthest away from the equator (at the poles). There are higher levels of sunlight in regions closer to the equator and lower levels at the poles. The results showed higher reports of depression among the workers who lived further from the equator, possibly due to the lack of sunlight exposure (Van de Vliert and Rentfrow, 2021).
Seasonal Affective Disorder: Treatments
There are many treatments available for SAD, as there now are for so many mental health disorders. SAD can be treated with psychotherapy, such as cognitive-behavioral therapy, as well as medication or supplements. SAD can also be helped with a treatment unique to the disorder: light therapy.
Since SAD is a specific type of depression, any treatment that helps with depression can be used to treat SAD. These treatments can be used alone or in combination with each other.
Light Therapy
Light therapy is a treatment method available to those with SAD that has been around since the 1980s. A person sits or stands in front of a specially-designed lightbox for 30 to 45 minutes a day, preferably in the morning. This helps supplement the loss of natural sunlight during the winter months.
Light therapy is a treatment method available to those with SAD, Wikimedia Commons.
Remember, low levels of sunlight can affect both melatonin production and vitamin D levels. While this therapy might seem quite different than other forms of treatment for someone with a mental health disorder, it is a recommended therapy for a reason! Light therapy will help your body produce healthy levels of melatonin and vitamin D, easing the symptoms of depression as a result.
Cognitive-Behavioral Therapy
Cognitive-behavioral therapy (CBT) is another treatment option for depression or SAD. This method of therapy is centered on identifying negative thoughts, feelings, and behaviors and changing them into positive thoughts, feelings, and behaviors. CBT is one of the most commonly used forms of psychopathology due to its combination of cognitive and behavioral approaches to therapy.
Medications and Supplements
Medications like antidepressants can also be helpful in treating SAD. The most common type of antidepressant is called a selective serotonin reuptake inhibitor (SSRI). These medications increase the levels of serotonin in the brain to help regulate mood.
While there is not much research that has been conducted on the efficacy of supplements in helping with SAD symptoms, there are still supplements to take. One could take vitamin D supplements, 5-HTP (to increase serotonin levels), or vitamin B12.
Seasonal Affective Disorder - Key takeaways
- Seasonal Affective Disorder (SAD) is a subtype of Major Depressive Disorder.
- To be diagnosed with SAD, someone has to be experiencing symptoms of depression in a consistent, seasonal cycle (mostly during winter).
- Two main symptoms of SAD are low mood most of the time and loss of interest in activities most of the time.
- Potential causes of SAD are lower levels of serotonin, issues with melatonin production, and vitamin D. deficiency.
- A unique treatment for SAD is light therapy, which is when someone stands near a special light box that simulates sun exposure.
References
- Evert Van de Vliert and Peter J. Rentfrow. "Who is more prone to depression at higher latitudes? Islanders or mainlanders?" Science Direct. Vol. 2. 2021.
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