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The Winter Blues: Seasonal Affective Disorder treatments

Seasonal affective disorder1 (SAD), is a type of depression that recurs at a certain time of the year. This is a reality for many people living in northern latitudes, such as Nordic countries, during the fall and winter months, when daylight hours are limited.

The eponymous “Winter Blues” is a type of SAD. Our moods can be easily affected by a change in temperature or climate. If you are inhabited in the northern hemisphere (in high latitudes), you have probably had bouts of the winter blues.  

What are the symptoms of SAD?

Typical symptoms2 of SAD include, lethargy or feelings of fatigue due to disrupted circadian rhythms and sleep, weight gain associated with overeating and increased cravings. SAD symptoms and its severity can vary, and coincide with that of major depressive disorder.

  • Feelingor being in a low mood
  • Lossof interest in pleasurable or everyday activities
  • Lethargy, or loss of energy despiteincreased sleep hours
  • Changes in appetite, overeating andincreased carbohydrate cravings
  • Increase in irritability, fidgeting or restlessness
  • Difficulty concentrating, thinking, or decision making
  • Decreased sex drive
  • Thoughts of self-harm
  • Changes in sleep, tend to be sleep deprived

Don’t panic! It is normal to experience some of these symptoms, especially so in the winter.

When should I see a doctor?

Should these symptoms persist, you find it difficult to cope with them, or they impact your day-to-day activities, you should consider seeing a doctor who will assess your situation.

What exactly causes SAD?

Scientists cannot pinpoint the exact cause of SAD, however we do know it is related to decreased exposure to sunlight during shorter winter days.  

A lack of sunlight or Vitamin D, prevents our hypothalamus from functioning properly, which in turn affects our,

· Serotonin3 production – serotonin is a hormone and neurotransmitter which regulates our mood, appetite and sleep, lowered serotonin production due insufficient sunlight is linked to depression

· Melatonin4 production – melatonin is a hormone which makes you feel sleepy and weakens energy levels, people who experience SAD overproduce melatonin

· Circadian rhythm5(our body’s internal clock) – our internal clock is attuned to changes in daylight, which may be disrupted by earlier sunsets and later sunrises

Light: Our key to happiness?

SAD can affect anyone, although it is more prevalent in women and those who live with less sunlight.

Luckily, there are several effective treatments for SAD, which do not involve pharmacology like antidepressants to improve our overall mood and mental well-being.

What can I incorporate into my life to manage SAD?

If light is what we lack, is it what we should incorporate back into our daily routines? The answer is: Absolutely!

The predictability and seasonality of SAD makes prevention of the disorder a key factor. One of the most effective prevention, as well as therapy for SAD, is light therapy6 or phototherapy.

It is recommended to receive light therapy early in the morning7. This can be in the form of outdoor sunlight (even if limited), or in front of a bright artificial lamp8, which consists of 10,000-luxcool-white fluorescent light.

The antidepressant effect of light, both natural and artificial, is optimal when administered according to our circadian cycle, around 8.5 hours after melatonin onset (this is usually the time we sleep).

Light therapy works by resetting our body's circadian rhythm, the internal clock which regulates our sleep and wake cycles. It can also boost our serotonin production, the neurotransmitter that is involved in regulating our mood.

Cognitive-behavioural therapy9 (CBT) is also a helpful treatment for SAD. CBT is a type of talk therapy that focuses on changing negative thought patterns and behaviours. It can help you identify and challenge negative thoughts, learn coping skills, and develop a more positive outlook. CBT can be done individually or in a group setting.

Exercise10 is also an important part of managing SAD. Regular physical activity has been shown to improve mood and reduce symptoms of depression. Aim to get at least 30 minutes of moderate-intensity exercise most days of the week. This could include activities such as brisk walking, cycling, swimming, or dancing. If you're not used to exercising, start slowly and gradually increase the intensity and duration of your workouts.

TLDR: 5 Take-home Tips on Managing Life with SAD

There are several other lifestyle changes that can help manage SAD. These include:

Getting enough sleep: Aim for 7-8hours of sleep each night and try to stick to a consistent sleep schedule.

Eating a healthy diet: Focus on eating a balanced diet that includes plenty of fruits, vegetables, whole grains, and lean protein

Make an effort to stay connected with friends and family, even if it means scheduling regular phone or video calls.

Meditation and Mindfulness: practice deep breathing, meditation and active yoga can help reduce stress and boost serotonin production11

Spending time outdoors: Whenever possible, try to spend time outside during daylight hours, even if it's just for a few minutes. This can help boost mood and improve sleep

Therapy: regular light therapy, accompanied by CBT for optimal results

Next time you’re feeling the effects of the Winter Blues, or if you are living with SAD, you can take these tips to alleviate your symptoms.By taking steps to manage SAD, you can improve your mood, boost your energy levels, and enjoy the winter months to the fullest!

Join our Beta Program at Waitasec for more tips on managing stress, depression, mental health andlearn about building better digital habits.


  1. Rosenthal, N. E., Sack, D. A., Gillin, J. C., Lewy, A. J., Goodwin, F. K., Davenport, Y.,... & Wehr, T. A. (1984). Seasonal affective disorder: a description of the syndrome and preliminary findings with light therapy. Archives of general psychiatry, 41 (1),72-80.
  2. F. Torres (2020). Seasonal Affective Disorder, The American psychiatric Association.
  3. Cowen, P.J., & Browning, M. (2015). What has serotonin to do with depression?. World Psychiatry, 14 (2), 158.
  4. Srinivasan,V., Smits, M., Spence, W., Lowe, A. D., Kayumov, L., Pandi-Perumal, S. R., ...& Cardinali, D. P. (2006). Melatonin in mood disorders. The World Journal of Biological Psychiatry,7 (3), 138-151.
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  6. Nussbaumer, B., Kaminski‐Hartenthaler, A., Forneris, C. A., Morgan, L. C., Sonis, J. H.,Gaynes, B. N., ... & Gartlehner, G. (2015). Light therapy for preventing seasonal affective disorder. Cochrane Database of Systematic Reviews, (11).
  7. Terman,J. S., Terman, M., Lo, E. S., & Cooper, T. B. (2001). Circadian time of morning light administration and therapeutic response in winter depression. Archives of general psychiatry, 58 (1), 69-75.
  8. Rohan, K.J., Mahon, J. N., Evans, M., Ho, S. Y., Meyerhoff, J., Postolache, T. T., & Vacek, P. M. (2015). Randomized trial of cognitive-behavioral therapy versus light therapy for seasonal affective disorder: acute outcomes. American Journal of Psychiatry, 172 (9), 862-869.
  9. Meyerhoff,J., Young, M. A., & Rohan, K. J. (2018). Patterns of depressive symptom remission during the treatment of seasonal affective disorder with cognitive‐behavioral therapy or light therapy. Depression and anxiety, 35 (5),457-467.
  10. Wipfli,B., Landers, D., Nagoshi, C., & Ringenbach, S. (2011). An examination of serotonin and psychological variables in the relationship between exercise and mental health. Scandinavian journal of medicine & science in sports, 21 (3),474-481.
  11. Cramer,H., Lauche, R., Langhorst, J., & Dobos, G. (2013). Yoga for depression: A systematic review and meta‐analysis. Depression and anxiety, 30 (11), 1068-1083.

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