Those familiar with major depressive disorder and its subtypes may have heard of Seasonal Depression or Seasonal Affective Disorder (SAD). This disorder is typically triggered by changing seasons and most commonly hits people by late fall. Its symptoms include loss of energy, an overall feeling of sadness, apathy, oversleeping and often weight gain.

Seasonal Affective Disorder or SAD is not to be confused with “winter blues”. While it is normal to feel a little blue in the colder months due to the gloomy weather and shorter daylight hours, SAD symptoms beyond these funky mood swings. Seasonal Affective Disorder is legitimately a kind of depression and affects your daily life, including your ability to function, your work and interpersonal relationships. Luckily, treatment can help most people get through this difficult time.

How to Identify Seasonal Affective Disorder?

Psychologists have classified Seasonal Depression as a type of Major Depressive Disorder. If you are suffering from Seasonal Depression, then you may experience some or all of the following symptoms as the seasons begin to change after fall:

  • Anxiety
  • Sadness
  • Feeling depressed almost every day
  • Lethargy
  • Trouble focusing
  • Feeling agitated
  • Craving for carbohydrates
  • Loss of interest in all activities
  • Sleeping challenges(oversleeping or sometimes insomnia)
  • Morbid thoughts
  • Heaviness in limbs

Seasonal Affective Disorder Symptoms

ShiftGrit Psychology & Counselling - seasonal affective disorder symptoms

Does it only occur in winter?

While not very common, there is a form of this disorder that occurs in late spring or early summer, known as “summer depression”.  The symptoms are similar to SAD except individuals may also complain of irritation, restlessness, anxiety, loss of appetite, episodes of violent behaviour, and trouble sleeping.

Diagnosis of Seasonal Affective Disorder

If you are experiencing some of the symptoms mentioned above, it’s best not to self-diagnose but seek expert advice. Begin by scheduling an appointment with your healthcare provider for a comprehensive evaluation. Sometimes there is an underlying physical cause for feelings of depression. Often seasonal depression is part of a more complex mental health issue.

Your primary provider will refer you to a mental health specialist based on your symptoms. The consulting psychologist or psychiatrist may consider your pattern of symptoms to identify if it is a seasonal disorder or some other challenge. Be prepared to share your experience, answer questions, and fill out questionnaires to get the right diagnosis.

There are no blood tests or scans to find out if it is seasonal depression but often providers recommend testing to rule out other medical conditions that cause similar symptoms.

Criteria for seasonal affective disorder diagnosis

  • To be diagnosed with seasonal depression, individuals are checked against the following criteria:
  • Symptoms of major depression or the more specific seasonal depressions listed above
  • A recurrence of depressive episodes in specific months/seasons for at least two consecutive years.
  • Higher frequency of depressive episodes happening during a specific season than the rest of the year.

Are some people more likely to suffer from SAD than others?

There is much research around seasonal depression and scientists have identified some causes that lead to this disorder. Research shows that people suffering from seasonal depression have reduced activity of serotonin(neurotransmitter) which is responsible for mood regulation. There is also a strong indication that sunlight controls the levels of molecules that help balance serotonin levels. For individuals with SAD, this regulation does not function, causing decreased serotonin levels in the winter months.

Other research has shown that people with SAD may produce too much melatonin, which is the hormone responsible for regulating the body’s seasonal day-night cycles. Individuals who have seasonal disorders tend to produce higher amounts of melatonin leading to extreme sleepiness. The changes in serotonin and melanin combined can disrupt normal daily rhythms. As a result, the individuals find it challenging to adjust to the seasonal changes, leading to sleep, behaviour and mood changes.

A lack of vitamin D in the body is also linked to Seasonal Affective Disorder. Vitamin D is known to promote serotonin activity. With less daylight in winter, especially in regions around the poles, individuals with SAD may have lower Vitamin D levels, aggravating the symptoms.

Those suffering from another mood disorder such as bipolar disorder or major depressive disorder are more likely to have seasonal affective disorder.

Scientists also believe that those with family members who have a history of SAD or other forms of mental health conditions are at risk.

People who live around the poles or in cloudy regions are also more likely to have seasonal depression owing to the lack of sunlight during winter in these places.

Treatment plan

The good news is that SAD can be treated and individuals see much improvement once they start their treatment plan. Your specialist will discuss your treatment options and you may often need a combination of the following:

Cognitive behavioural therapy: CBT is a type of talk therapy and research has shown it treats SAD effectively, producing the most long-term effects of all the treatment approaches.

Light therapy: Light therapy also known as phototherapy uses bright lights to improve the symptoms. It adjusts your biological clock aligning your circadian rhythms and balancing the serotonin circuitry in the brain.

Medication: Often providers suggest antidepressants in combination with CBT or light therapy.

Vitamin D supplements: Vitamin D supplements can help alleviate the symptoms.

Outdoor activity: Getting more sunlight is a sure-shot way to improve mood and symptoms. Individuals are asked to get out more during the day and increase their sunlight exposure.