woman standing in snow at dusk looking depressed

What Is Seasonal Affective Disorder (SAD)?

Seasonal Affective Disorder (SAD) is a type of depressive disorder related to seasonal variations of light. As seasons change, there is a change in sunlight which disrupt our “internal biological clock” or circadian rhythms – which tell us when it’s to sleep and to wake up.

The most common type of SAD is winter depression. As many as 6 of every 100 Americans have winter depression. While 10% to 20% experience milder SAD – or “winter blues”. SAD is more common in women, and it usually doesn’t start in people younger than 20 years old. The most difficult months for SAD are between September and April, in particular during December, January and February. 

It is most prevalent in northern geographic areas such as US and Canada, but extremely rare in those living in tropical areas where daylight hours are long, constant and extremely bright.

Common symptoms of SAD

Common symptoms of SAD include the following:

  • Sleep problems. Usually desire to oversleep and difficulty staying awake but, in some cases, disturbed sleep and early morning wakening
  • Lethargy and loss of energy. Feeling of fatigue and inability to carry out normal routine
  • Overeating. Craving for sweet and starchy foods, usually resulting in weight gain
  • Depression. Melatonin, a sleep-related hormone that’s also linked to depression, has been linked to SAD. There is an increased production of melatonin in the dark, thus, during the long nights of winter. 
  • Social problems. Irritability and desire to avoid social contact and increased sensitivity to social rejection
  • Difficulty concentrating and processing information
  • Anxiety. Tension and inability to tolerate stress
  • Loss of libido. Decreased interest in sex and physical contact
  • Mood changes. Hypomania, or hyperactivity
  • Headaches

How To Treat SAD

There are several options of treating SAD. Those suffering from SAD might want to consider the following:

  • Phototherapy or bright light therapy has been shown to suppress the brain’s secretion of melatonin. It consists of sitting a few feet away from a special lamp that’s 10 to 20 times brighter than ordinary indoor lights, allowing the light to shine directly through the eyes, for 30 or more minutes each day,
  • Medication. There are prescribed antidepressant drugs for SAD, but people should be wary of unwanted side effects.
  • Psychotherapy or counseling helps the sufferer identify and modify negative thoughts and behaviors that may play a role in bringing about signs and symptoms of SAD. It helps the person to relax, accept their illness and cope with its limitations.
  • Other treatments. For mild symptoms, spending time outdoors on sunny days, even during winter helps. Also, by arranging homes and workplaces so as to receive more sunlight. Daily exercise and balanced diet help manage stress. If possible, take winter vacations in sunny, warm locations.