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Seasonal Affective Disorder (SAD)

What causes "the winter blues"? Get the answers in our guide.
Seasonal affective disorder (SAD) causes, symptoms, and treatments

We may all feel a touch of the winter blues during those cold gray months, but for people with seasonal affective disorder (SAD), winter depression happens each year and it can have a marked impact on their well-being. A type of clinical depression, SAD occurs at the same time each year, usually from late autumn until spring and results in fatigue and a low mood. Between two and three percent of the population has SAD, according to the Canadian Mental Health Association, while another 15 percent have a milder form, called the “winter blues.” The condition is more common in northern countries, like Canada, where the winter days are shorter. In rare cases, SAD occurs in the summer.

SAD causes It is possible that the lack of sunlight in the winter months disrupts the body’s biological clock or circadian rhythm, which governs sleep and waking. Reduced sunlight may also cause a drop in the brain chemical serotonin, which can lead to depression. The risk of developing SAD increases with age. SAD affects more women, and a family history of the condition increases a person’s risk.

SAD symptoms The symptoms of SAD are similar to other types of depression, which can make it difficult to diagnose. Symptoms usually happen for at least two consecutive winters and may include changes in appetite, with cravings for sweet or starchy foods, weight gain, decreased energy, fatigue, tendency to oversleep, trouble concentrating, irritability, avoidance of social situations and feelings of anxiety and despair. When spring arrives, SAD symptoms generally disappear. Summer depression symptoms include difficulty sleeping, lack of appetite and weight loss.

SAD diagnosis/tests If you're experiencing depression symptoms, talk to your doctor who may refer you to a psychiatrist for diagnosis and treatment. SAD is similiar to depression so she will look for symptoms of depression and ask you about the timing of these symptoms as they relate to the seasons.

SAD treatment People with mild SAD symptoms may benefit from spending time outdoors during the day to receive maximum sunlight. Sitting close to windows, installing skylights and lamps and exercising outdoors in daylight relieves stress and lifts mood. Taking a winter vacation in a sunny location often temporarily relieves SAD symptoms. Light therapy has been proven effective at treating the symptoms of SAD. Sitting beside a special fluorescent light box for several minutes daily appears to change the brain chemicals linked to mood. For people with more severe cases of SAD, antidepressants and therapy may relieve winter depression symptoms. Psychotherapy, particularly cognitive behavioural therapy, may also be helpful for winter depression by helping sufferers identify and change behaviours and thoughts that make them feel worse.

SAD prevention The exact cause of SAD is still not fully understood, but making lifestyle changes, such as exercising more frequently, practicing stress management exercises, spending more time outside and increasing the amount of light inside may help guard against the condition. Getting an early diagnosis is also helpful to keep the condition from significantly disrupting your life.



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