By Wesley Gallagher

The onset of winter brings many things – snowy days, evenings by the fire, holiday coziness and warm sweaters, to name a few. For some people, however, winter brings an unwelcome change in mood. The “winter blues” are a common malaise brought on by the winter season, but many people suffer from a more serious disorder called Seasonal Affective Disorder (SAD).1

What Is SAD?

Frowny face in the snowAccording to the website Psycom, SAD is a category of depression that comes on in particular seasons of the year, most often starting in the fall and increasing in the winter. Despite common perception, it is not a lighter version of major depression, but a subtype of clinical depression, in which depression goes into a type of remission during off-seasons.2

The American Academy of Family Physicians estimates that about four to six percent of US residents suffer from SAD, and as many as 20 percent suffer from a mild form of it that comes with shorter and colder days.3 Young females and people who live farther from the equator or with a family history of depression are at greater risk of suffering from SAD.2

Common symptoms of SAD include the following:

  • Negative changes in mood
  • Feelings of hopelessness
  • Less energy
  • Difficulty concentrating
  • Changes in sleep patterns and appetite
  • Loss of interest in enjoyable activities
  • Suicidal thoughts

The winter form of SAD may also bring with it the following symptoms:

  • Feeling of heaviness in arms and legs
  • Oversleeping
  • Weight gain or carb cravings
  • Problems with relationships

If you notice these symptoms happening regularly during certain seasons over a period of two years, you might qualify for a diagnosis of SAD.2

What Causes SAD?

While a definitive cause for Seasonal Affective Disorder hasn’t been established, researchers have found a few factors that probably contribute to the disorder.

According to an article in The Atlantic, the leading theory is the “phase-shift hypothesis,” in which our circadian rhythm (our internal biological clock that regulates energy, hunger and sleep) falls out of sync with the time of day as the days become shorter. Levels of melatonin, the hormone that makes us tired, usually rise at night when it gets dark, and bright sunlight in the morning suppresses it. When the circadian rhythm is slow, melatonin levels are higher in the morning, causing grogginess. The connection between this disruption and depression is unclear, but it might be related to negative thoughts about tiredness leading to depressed mood, lack of appetite and other symptoms.1

Another theory involves active thyroid hormone, which regulates several behaviors and bodily processes. High melatonin levels in the morning due to later sunrise suppress the creation of active thyroid hormone, causing changes in mood, appetite and energy. Active thyroid hormone influences serotonin, a mood-regulating hormone, which is one way this process may contribute to SAD.1

Whatever the precise cause, evidence points to some or all of these factors playing a role in the development of SAD. So what should you do if you think you could be suffering from it?

Ways to Treat SAD

While SAD can be quite serious, there are steps you can take to manage or overcome it. If you feel symptoms coming on or know that a certain season always brings depression, take action as soon as possible.

Everyday Health lists several ways to effectively treat SAD:

  • Talk to a professional: If you suspect you’re suffering from SAD, talk to your physician or a mental health professional. They can diagnose the disorder and discuss treatment options.
  • Get moving: Exercise can alleviate symptoms, especially if done outside where you’ll also get some sun.
  • Catch some rays: Go outside as often as you can, and keep blinds open when you’re inside. Light therapy boxes, which mimic sunshine, have been shown to stimulate circadian rhythms and suppress melatonin, especially when used in the morning. Dawn simulating alarm clocks have also been found effective.
  • Stick to a schedule: Regular schedules improve sleep, which can alleviate SAD symptoms, and expose you to light at consistent times of day. Eating regularly can curb overeating.
  • Go south: Even a short vacation to a warmer climate can create a lasting boost in mood and alleviate symptoms of SAD.
  • Write about it: Keeping a journal of your thoughts can positively affect your mood by getting negative thoughts out of your system and onto the page. Try writing for 20 minutes a day about any thoughts, feelings or concerns you’ve been having.
  • Get your vitamin D: Talk to a doctor about testing your vitamin D levels. Vitamin D has been shown to improve depression, so a supplement might help.
  • Consider medication: If other treatments fall short, talk to your doctor about taking antidepressants to regulate your mood and alleviate depression. Medication may be just what the doctor ordered.3


1 Geddes, Linda. “Will Norway Ever Beat the Winter Blues?The Atlantic, March 14, 2017.

2 Lieber, Arnold, MD. “A Guide to Treating SAD.” Psycom, Accessed November 28, 2017.

3 Orenstein, Beth. “12 Ways to Ease Seasonal Depression.” Everyday Health, June 5, 2017.