What is seasonal affective disorder?

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When the seasons shift from summer to fall, many people feel excited, refreshed and eager for a change. But for some people, the changing season can bring on unexpected feelings of despair that go well beyond the occasional "winter blues."

At SIU Medicine, we want people to be aware of seasonal affective disorder, or SAD. If left untreated, this condition can make it extremely difficult for a person to function throughout the fall and winter months. Keep reading to learn more and discover how we can help you or a loved one who may be struggling.

What is seasonal affective disorder (SAD)?

Seasonal affective disorder (SAD) is a type of depression related to changing seasons. It can occur on its own or in conjunction with other mental health conditions, such as bipolar disorder or major depression.

Some people with SAD are affected during the transition from spring into early summer. However, it's much more likely to occur in the fall and winter months. Doctors believe SAD occurs as a result of the shorter days during the fall and winter. Reduced sunlight exposure can disrupt the body's internal clock (circadian rhythm), interrupt normal sleep patterns and lead to a drop in mood-influencing hormones including serotonin and melatonin.

You may be more at risk for developing SAD if you have other mental health conditions, have a family history of the condition, are a younger adult, are female or live in higher latitudes further away from the equator.

Signs and symptoms of SAD

SAD can affect people differently and range from mild to nearly debilitating. Common signs and symptoms to look out for include:

  • Feeling depressed or down on most days
  • Having low energy or feeling sluggish, irritable or agitated
  • Sleeping too much or not sleeping enough
  • Eating too much or not eating enough
  • Losing interest in previously enjoyable activities
  • Fluctuations in weight (gain or loss)
  • Having poor concentration
  • Feeling a sense of hopelessness, guilt, or unworthiness
  • Thinking more frequently about suicide or death

The key hallmark of these symptoms is that they occur in relation to changing seasons—again, usually in late fall and into winter. Symptoms can start gradually and grow worse as the season goes on, but usually go away by the time spring and summer come along.

How SAD is diagnosed and treated

SAD can only be diagnosed by a licensed medical professional, but it's absolutely important to seek professional help if you're concerned about any symptoms. Untreated SAD can lead to a range of consequences or complications including social isolation, substance abuse and even attempted suicide.

Right now, SAD is treatable through a combination of evidence-backed therapies, including psychotherapy, antidepressant medications and light therapy (which exposes you to a special type of artificial light as a "stand-in" for the sun). Regular exercise is also considered an effective and inexpensive way to alleviate SAD symptoms, elevate mood and improve sleep.

If you have SAD

If you or a loved one is struggling with symptoms of depression or are worried about the "winter blues," contact SIU Medicine at 217-545-8000 to schedule an appointment with one of our Central Illinois mental health providers. We're here to connect you and your loved ones with innovative, private, and customized services that can help you start feeling better and more in control of your life again. Call today.

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