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Coping with Seasonal Affective Disorder

25 January 2018

It’s quite common to be impacted by the transition of seasons. Seasonal Affective Disorder, or SAD, is a type of depression that occurs during the same season each year. You may have SAD if you felt depressed during the last two winters but felt much better in spring and summer. Some people may have SAD during the summer months.

Experts aren't sure what causes SAD. But they think it may be caused by a lack of sunlight.

Lack of light may:

  • Upset your "biological clock," which controls your sleep-wake pattern and other circadian rhythms.
  • Cause problems with serotonin, a brain chemical that affects mood.

If you have SAD, you may:

  • feel sad, grumpy, moody, or anxious;
  • lose interest in your usual activities;
  • eat more and crave carbohydrates, such as bread and pasta;
  • gain weight;
  • sleep more but still feel tired; or
  • have trouble concentrating.

Symptoms come and go at about the same time each year. Most people with SAD start to have symptoms in September or October and feel better by April or May.