Seasonal Affective Disorder   

Seasonal Affective Disorder (SAD) is perceived as a form of major depression that occurs in a seasonal pattern. It is a type of depression that influences people living in countries that are away from the center of the Earth. It commonly occurs during the Winter months and usually resolves during the Spring. Additional terms used for Seasonal Affective Disorder (SAD) are winter depression or seasonal depression. As the changes in daylight and darkness change and darkness become longer, some people consider it as a shift in their internal biological clock and this disturbance in the circadian rhythm can considerably disrupt mood.

Seasonal Affective Disorder (SAD) is four times more prevalent in women when compared to men, and it is more likely to occur between 18 and 30 years of age. People living further away from the equator in the northern latitudes are most prone to develop the disorder. It starts and ends almost at the same time every year. People have trouble regulating hormonal serotonin levels which are believed to be responsible for regulating moods and promoting positive and happier emotional states.

Signs of Seasonal Affective Disorder (SAD) can be difficult to diagnose if it occurs along with other mental health issues such as chronic depression, bipolar disorder, attention deficit hyperactivity disorder, alcoholism, and eating disorders. 


Signs and symptoms of Seasonal Affective Disorder (SAD)

Signs and symptoms of Seasonal Affective Disorder (SAD) may include:

  • Feeling miserable and depressed during most of the day, nearly every day
  • Loss of interest in almost all activities that you enjoy
  • Having low energy
  • Having difficulty sleeping 
  • Excessive weight loss, poor diet, and other eating disorders
  • Feeling restless
  • Having trouble concentrating
  • Feelings of hopelessness, worthlessness, or unnecessary guilt
  • Having thoughts of death or suicidal thoughts

Winter Depression Symptoms linked with winter onset of Seasonal Affective Disorder is sometimes referred to as winter depression and include: 

  • Hypersomnia (Oversleeping)
  • Changes in appetite, particularly a desire for foods having a higher content of carbohydrates
  • Sudden weight gain
  • Exhaustion, low energy, seasonal affective disorder fatigue

Summer Depression Symptoms linked with the summer onset of Seasonal Affective Disorder is referred to as summer depression and include: 

  • Insomnia (Trouble in falling asleep)
  • Loss of appetite
  • Sudden weight loss
  • Distress or nervousness

Changes in Seasonal Bipolar Disorder (SAD) Symptoms

In some individuals who suffer from Seasonal Bipolar Disorder, the Spring and Summer can lead to seasonal depression symptoms of hypomania or mania, and the season of Winter can lead to prolonged periods and signs of seasonal depression.

Seasonal Affective Disorder (SAD) Risk Factors

Seasonal Affective Disorder (SAD) is more common in younger people and females. You can be at a higher seasonal affective disorder risk factor for developing the condition if you:

  • Have any other type of mood disorder such as Seasonal Affective Disorder (SAD) and Bipolar Disorder.
  • Have relatives with psychological disorders, such as depression.  
  • Are living in regions of higher latitudes (e.g. north of the equator such as Alaska).
  • Live in regions that typically have cloudy days. 

Conditions with Seasonal Affective Disorder (SAD):

People who suffer from Seasonal Affective Disorder (SAD)may also have other conditions such as: 

  • Eating disorders such as Bulimia Nervosa or Anorexia nervosa
  • Anxiety disorders
  • Attention Deficit Hyperactivity Disorder (ADHD).
  • Generalized Anxiety Disorder
  • Panic disorder

Causes of Seasonal Affective Disorder

  1. Changes in Biological clock: When someone has a smaller amount of exposure to the sunlight their biological clock swings. This internal clock controls sleep, mood, hormones, etc. When it changes, people may have trouble regulating their moods.
  2. Imbalance of chemicals in the brain: Neurotransmitters such as serotonin hormones, which add to the state of happiness, when they are decreased people are at higher risk for seasonal depression.  Sunlight is known to help regulate serotonin so lesser exposure to sunlight in the winter can make the situation worse.
  3. Deficiency of Vitamin D: Vitamin D boosts serotonin levels and the major source of Vitamin D is the sun. Less sun in the winter leads to the deficiency in Vitamin D which affects the level of serotonin and hence affects mood.
  4. Overproduction of Melatonin: Melatonin is a hormone that affects sleep patterns. The lack of sunlight may lead to an overproduction of melatonin in some people which makes them sluggish and sleepy usually during winter.
  5. Negative thoughts: People with Seasonal Affective Disorder often have negative thoughts, stress, and anxiety even before the onset of winter. Researchers are not sure if these negative thoughts and panic are a causative factor of seasonal depression or not.

Complications of Seasonal affective disorder

Just like the other types of depression, if treating the seasonal affective disorder and treating seasonal depression left untreated, can lead to other problems such as: 

  • Social isolation or social withdrawal
  • Problems at school or work
  • Drug or substance abuse
  • Other psychological disorders (i.e. panic or anxiety issues)
  • Suicidal thoughts 

Seasonal Affective Disorder Diagnosis

  • Physical exam: Your doctor may perform a physical exam to assess your health. With some individuals, seasonal depression signs and symptoms can be associated with a physical health issue. That’s why, for a better seasonal affective disorder diagnosis, this physical exam is done.
  • Lab tests: Your doctor may run a complete blood count (CBC) or test the thyroid to see if it is functioning properly or not for the best seasonal affective disorder diagnosis.
  • Psychological assessment: A psychologist or other mental health professional will assess for seasonal depression symptoms to see if the seasonal affective disorder diagnostic criteria are met for this seasonal affective disorder diagnosis. 

How to prevent Seasonal Affective Disorder

After seasonal depression diagnosis, the affective patients must follow these steps.

  • Spend time outside the home on daily basis, even when it is cloudy or raining. The effects of daylight are still very helpful. If it is too cold outside, you can open your window blinds and sit by a sunny window to get some effects of the sun.
  • Using a 10,000-lux light box during the fall season, even before the sensation of winter
  • Eat a balanced diet 
  • Exercising for 30 minutes four to five times a week helps release endorphins which are “happy hormones.”   

Seasonal Affective Disorder Treatment:



If your depressed mood is prominent, and you need sad symptoms treatment, you may be prescribed an anti-depressant. When mood improves usually during the Spring, you can be weaned off the medication. 

Light therapy:

Even a short walk in the sunlight can be helpful. Try to expose yourself to sunlight every day the sun is out, and if it is too cold outside, sit near windows with the shades up. 


Cognitive Behavioral Therapy (CBT) is a therapy that has been proven effective for seasonal affective disorder symptoms.

Self-help behaviors: 

The following activities may help during the acute phase of the disorder: 

  • Regulate your sleep cycle. 
  • Go for daily walks even on cloudy days
  • Regular exercises
  • Daily exposure to the sun
  • Enhance lighting inside the home