Seasonal Depression: What Is It and How Do I Treat It?


Do you feel more sad and tired during the winter months? Do your energy and enthusiasm levels begin to drop around the fall season? It’s normal to experience some “winter blues” during the colder months, but if you’re experiencing intense, persistent feelings of sadness, lethargy, exhaustion, and other symptoms that impair your daily life, you could be experiencing seasonal depression.

Defining Seasonal Affective Disorder

Seasonal depression, also known as seasonal affective disorder or SAD (not to be confused with Social Anxiety Disorder SAD), is a type of depression that correlates with changes in the seasons. The American Psychiatric Association (APA) estimates that SAD affects about 5% of adults in the United States, with more women than men reporting it.

The most common type of seasonal depression is triggered by the onset of fall and winter, but spring and summer-related depression is also reported. Symptoms may initially be mild but can worsen as the season continues.

Symptoms of SAD

The symptoms of seasonal affective disorder overlap with the symptoms of major depressive disorder, however, these two types of depression should not be confused with each other. Symptoms of seasonal affective disorder include:

  • Persistent feelings of sadness, melancholy, or emptiness.
  • A decrease or lack of interest in hobbies and activities previously enjoyed by the sufferer.
  • Feeling exhausted and lacking energy.
  • Experiencing insomnia or sleeping too much.
  • A change in appetite and weight gain or weight loss.
  • Feelings of guilt, worthlessness, and hopelessness.
  • Difficulty concentrating, remembering, and focusing.
  • Thoughts or discussion about suicide, or suicide plans and attempts.

**On top of these symptoms, there are unique symptoms tied to winter seasonal affective disorder:

  • Sleeping too much.
  • Tiredness and exhaustion, despite oversleeping.
  • Overeating, with a particular craving for carbohydrate-rich foods.

**Symptoms specific to summer-related seasonal depression include:

  • Insomnia.
  • Reduced appetite and weight loss.
  • Feelings of anxiety and distress.

What Causes Seasonal Depression?

Researchers aren’t sure what exactly causes seasonal depression, but there are certain theories about what contributes to its development:

  • Circadian rhythm disruption - Lower levels of natural sunlight during winter can disrupt the body’s biological clock which helps to regulate a person’s hormones, mood, and sleep. When this disruption to the circadian rhythm happens, it can affect a person’s physical and emotional state.
  • Serotonin production in the brain - Serotonin is a chemical that plays a role in mood regulation. Sunlight helps to promote serotonin levels so a reduction in sunlight can cause a drop in serotonin, resulting in emotional imbalance.
  • A lack of vitamin D - Vitamin D also helps to regulate serotonin production. Less sunlight during winter can cause a vitamin D deficiency in our bodies, impacting our serotonin production.
  • Overproduction of melatonin - Melatonin is a natural chemical in our bodies that assists with regulating our sleep patterns. Lower sunlight levels in winter mean it's darker during the day, which can cause an overproduction of melatonin in the body. This can result in the person feeling more tired than usual.

**Certain factors can make a person more at risk of developing seasonal depression:

  • Genetics - Having an immediate family member who suffers from seasonal affective disorder can increase your chance of developing it.
  • Personal history - Being diagnosed with major depression or bipolar disorder can put you at higher risk of experiencing SAD.
  • Location - People who live far north or south of the equator are more likely to experience seasonal affective disorder, due to the extremely low levels of sunlight during winter and high levels during summer.

Treating SAD

If you are experiencing the symptoms of seasonal depression, do not ignore them or brush them off as seasonal woes. They could worsen over time and lead to secondary problems, such as alcoholism or drug abuse if left untreated.

Talk to your doctor or a psychologist about what you’re experiencing. They will likely first test you to see if your symptoms stem from another underlying medical condition before testing for seasonal affective disorder. Treatments for SAD include:

  • Phototherapy - phototherapy, or light therapy, involves sitting in front of a specially-developed light box that emits a very bright light for a scheduled time each day.
  • Medication - medication, particularly antidepressant medication, can prove effective in treating seasonal depression.
  • CBT therapy - cognitive-behavioural therapy, or talk therapy, can help to treat SAD symptoms.

Remember to never take any medication or undertake treatment that’s not directly prescribed to you by a health professional.


While not a treatment, making changes to your lifestyle can help to manage the effects of seasonal depression. Exercising, eating a balanced diet, and keeping a busy schedule that doesn’t allow you to stay indoors for long periods can play a role in improving your overall mood.

Never feel like it’s your fault or that something is wrong with you if you are experiencing seasonal affective disorder. It’s a treatable condition, and reaching out to a doctor or mental health professional can give you the resources you need to overcome seasonal affective disorder.

Are you ready to tackle your feelings of depression? Sign up for our engaging and empathetic online course for depression here.