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Seasonal Depression (Seasonal Affective Disorder)

Do the bleak winter months get you down more than you think they should? Maybe you have seasonal depression, also known as seasonal affective disorder or SAD. Seasonal depression is a mood disorder that happens every year at the same time. A rare form of seasonal depression, known as "summer depression," begins in late spring or early summer and ends in fall. But in general, seasonal affective disorder starts in fall or winter and ends in spring or early summer.

What Causes Seasonal Affective Disorder?

There are two seasonal patterns with SAD. One starts in the fall and continues through the winter, and the other starts in late spring or early summer. The fall-onset type of SAD, often referred to as "winter depression," is better known and easier to recognize -- and we know more about it than we know about its counterpart.

Hormones manufactured deep in the brain automatically trigger attitudinal changes at certain times of year. Experts believe that SAD is related to these hormonal changes. One theory is that reduced sunlight during fall and winter leads to reduced production of serotonin in the the brain. Serotonin is a neurotransmitter that has a soothing, calming effect. The result of there not being enough serotonin is feelings of depression along with symptoms of fatigue, carbohydrate craving, and weight gain.

Because foods high in carbohydrates (chips, pretzels, cookies) boost serotonin, it is thought that they have a calming, soothing affect on the body and mind.

SAD usually starts in young adulthood and is more common in females than in males. Some people with SAD experience very mild symptoms and feel out of sorts or irritable. Others have debilitating symptoms that interfere with relationships and productivity.

Because the lack of enough daylight during wintertime is related to SAD, it is seldom found in countries within 30 degrees of the equator, where there is plenty of sunshine year round.

What Are the Symptoms of SAD During Winter?

People with SAD have many of the normal signs of depression, including:

  • Decreased levels of energy
  • Difficulty concentrating
  • Fatigue
  • Increase in appetite
  • Increased desire to be alone
  • Increased need for sleep
  • Weight gain

What Are the Signs of SAD During Summer?

Symptoms of summer SAD include:

  • Decreased appetite
  • Trouble sleeping
  • Weight loss

How Is Seasonal Affective Disorder Diagnosed?

It is very important that you do not diagnose yourself with seasonal affective disorder. If you have symptoms of depression, see your doctor for a thorough assessment. Sometimes, physical problems can cause depression. But other times, symptoms of seasonal depression are part of a more complex psychiatric problem. A health professional should be the one to determine your level of depression and recommend the right form of treatment.

How Is Seasonal Depression Treated?

There are different treatments for seasonal depression, depending on the severity of the symptoms. Also, if you have another type of depression or bipolar disorder, the treatment may be different. Many doctors recommend that patients with SAD try to get outside early in the morning to increase their exposure to natural light. If this is impossible because of the dark winter months, antidepressant medications and/or light therapy (phototherapy) may help.

WebMD Medical Reference

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