Seasonal Affective Disorder

Seasonal affective disorder (SAD) is a mood condition affected by changes in season. It is a type of depression usually linked to fall and winter months. However, for a small number of people it can occur in spring and summer. Seasonal affective disorder is usually experienced with the onset of a major depressive episode that is triggered at a specific time of the year. Generally, those affected by SAD report good mental health throughout the rest of the year.

Seasonal affective disorder was first formally recognized as an adverse state of mental health by the National Institute of Mental Health in 1984. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) lists it under recurrent major depressive states, but adds a “seasonal pattern” specifier, pointing out that it occurs at a particular time of the year.


Many people experience a change in mood during the winter as a result of fewer daylight hours, low vitamin D production, and less physical activity. The most common symptoms of SAD are similar to the symptoms of major depression. They include:

Loss of pleasure or interest in everyday activities

Feelings of sadness, despair, worthlessness, or guilt

Feeling anxious and overly worried

Increased irritability


Increased appetite and weight gain

Reduced appetite and weight loss


Low self-esteem

Reduced libido

Sleep issues

At the behavioral level, a person experiencing seasonal affective disorder may be less active than usual. They may avoid social interactions and activities. He or she may feel excessively sleepy and tired (hypersomnia) for most of the day. Difficulty with concentration is also very common. A change in appetite may occur, which causes a person to gain or lose weight in an unhealthy way. SAD can affect a person’s social, family, and work life, causing him or her to withdraw from some or all aspects of that part of life.


According to an article published in the journal of Psychiatry, about 10% to 20% of recurrent depressive episodes follow a seasonal pattern. In the United States, the prevalence of seasonal affective disorder varies, often determined by latitude. It ranges from 9.7% in New Hampshire to 1.4% in Florida, demonstrating that people living in areas where seasonal daylight hours decrease are more likely to experience this condition. Overall, SAD affects about 6% of Americans, with more women than men experiencing symptoms. Community-based studies estimate that the prevalence of SAD approaches 18% in northern latitudes such as Alaska and Scandinavia.


Available treatment options for this condition include light therapy (phototherapy), nutritional changes, and psychotherapy with or without medication. Light therapy is a common treatment for SAD. The person in light therapy treatment sits near a light box that produces “LUX” units, or Luminous Emittance in amounts similar to that of the sun, mimicking natural outdoor light. Light therapy sessions generally last about 10 to 15 minutes at the outset, and gradually increase depending on the severity of a person’s experience with SAD. Although the exact etiology of SAD is still unknown, most researchers believe light therapy reduces a person’s symptoms by balancing the body’s circadian rhythm and increasing the amount of serotonin in the brain, a neurotransmitter that has a direct impact on mood and tends to be reduced in the winter for many people.

Antidepressants are also frequently prescribed to help alleviate severe symptoms of depression and SAD. Many people find lasting results are achieved through participation in psychotherapy, perhaps in combination with medication or light therapy. Cognitive behavioral therapy (CBT), for example, has been shown in some studies to be just as effective as antidepressant medication for treating depression. Therapies like CBT often help people understand and reorganize their thought patterns when living with a condition like SAD or depression, leading to healthier methods of coping than relying on medication alone to treat symptoms.


There are many preventative measures that can help people transition into the winter months without experiencing negative changes in mood. These can include:

-Try to spend some time outdoors each day, even on a cloudy day or in the dark.

-Consider investing in a light box to use before the fall and winter months set in, particularly if you have experienced SAD in the past.

-Engage in some form of physical activity at least 30 minutes a day, five days a week. Regular exercise helps balance hormones and neurotransmitters that affect your mood.

-Maintain an active social life.

-Ensure you are getting the foods you need to stay healthy and keep your mood in check. Consider talking to your doctor about checking your nutrition levels to spot any deficiencies that may lead to or exacerbate the symptoms of SAD.

-Consider getting involved in a winter sport such as skiing, ice skating, or snowshoeing.

-Maintain a regular sleep schedule.

-Find a qualified therapist with whom you can discuss your symptoms, learn coping skills and develop a good self-care routine.

Speak Your Mind


1638 Eagle View Drive
Homer, AK 99603
(907) 602-2578

Got Questions?
Send a Message!

By submitting this form via this web portal, you acknowledge and accept the risks of communicating your health information via this unencrypted email and electronic messaging and wish to continue despite those risks. By clicking "Yes, I want to submit this form" you agree to hold Brighter Vision harmless for unauthorized use, disclosure, or access of your protected health information sent via this electronic means.