In recent years, society has become far more accepting of depression as a serious medical condition, and how it deserves professional attention in order to provide relief for those suffering with it. Much exists that we still do not completely understand, which is why we need to gain awareness around every form of depression as much as possible.

In this blog, Team Med are exploring Seasonal Affective Disorder.

Seasonal Affective Disorder Defined

If you, or someone you know, suffers from a yearly feeling of ‘winter blues’ or a distinct funk that is difficult to climb out of, it is possible to work through it. This is known as Seasonal Affective Disorder (SAD), which is form of depression that relates to the changing seasons. SAD will usually begin and end around the same time every year, with most people experiencing their symptoms at the start of autumn and carrying through until the winter months, particularly the feeling of sapped energy and a general moodiness. This being said, it is also entirely possible for people to have SAD-caused depression during spring and summer.

Causes of SAD

Research into SAD is yet to offer a definitive cause(s), however several factors have been found to play a role in bringing it about, such as:

  • Serotonin Levels: Serotonin is a chemical within the brain (known as a neurotransmitter) that is responsible for affecting a person’s mood, which means it may therefore play a role in causing SAD if there is a significant drop. Several factors can affect serotonin, such as the amount of exposure to sunlight.
  • Melatonin Levels: Similar to sunlight affecting serotonin levels, the change in seasons has been seen to disrupt the body’s balance of melatonin, a hormone secreted that plays a vital role in mood and sleep cycles.
  • Circadian Rhythm: A person’s circadian rhythm is essentially an internal clock that continues to tick inside your brain, keeping track of the periods and intervals between sleep and alertness – essentially, your sense of day and night. As seasons change, so do the periods of daylight, and so, among other elements, reductions in sunlight may lead to disruptions to your circadian rhythm, triggering feelings of depression.

Risk Factors

Again, there is still more that needs to be understood about SAD, however certain risk factors and correlations have been identified. For example, SAD is diagnosed far more often in women than men, and in younger people rather than adults. Other factors include:

  • Having a family history of blood relatives suffering from SAD or another type of depression.
  • Existing depression or bipolar disorder can have their symptoms worsened during the changing seasons.
  • Similarly, with the lack of sunlight, the further people live from the equator, both north and south, the higher their chances of suffering from SAD, due to darker winters and longer days throughout summer.

Symptoms of SAD

As mentioned above, SAD is most commonly experienced during late autumn and throughout winter, which means symptoms will usually subside as spring and summer roll in. That being said, there are many people who suffer throughout the hotter months, and will experience slightly altered symptoms. Regardless, symptoms will generally start out mild and only slight hindrances, before they intensify as the months carry on.

Common symptoms for all those suffering from SAD revolve around feelings of worthlessness, hopelessness, guilt, and the desire to self-harm. However, more specific symptoms are:

Autumn and Winter SAD


  • Weight Gain
  • Excessive Sleeping
  • Tiredness or a lack of energy
  • Change in appetite


Spring and Summer SAD


  • Insomnia
  • Weight loss
  • Agitation or anxiety



It is imperative that seasonal affective disorder and its symptoms are addressed in a serious manner. Without effective attention and treatment, SAD can significantly worsen and create severe issues in later life, such as trouble in your work or at school, substance abuse, suicidal tendencies, social withdrawal, and a range of other mental health disorders.

It is very easy to write off bad thoughts and feelings, but if they persist for weeks and months on end, a doctor should always be consulted. This will expose you to proven methods that will work toward moderating your mood and motivation throughout the entire year.