Minnesotans at Greater Risk of Seasonal Depression

By Dr. David Adson, M.D.
(Dec. 5, 2004; Updated Oct. 24, 2005)

For many people with depression, winter may be an especially challenging time of year. Those suffering from major depression or bipolar disorder may have worsening symptoms as exposure to daylight shortens and temperatures drop.

With short winter days, residents of northern states such as Minnesota are at greater risk for seasonal changes in depression symptoms. These seasonal mood patterns are referred to as Seasonal Affective Disorder (SAD) and women are about twice as likely to suffer from this and other mood disorders. Although the exact cause of SAD is not known, research has shown that melatonin (a hormone affected by light) and brain serotonin levels are lower in the winter and spring.

SAD is a recurring depression with a clear seasonal pattern that occurs in about 2 to 3 percent of the general population. However, less severe mood changes with the seasons are more common and may not meet the full criteria for SAD. A study in Maryland and reported in the Archives of General Psychiatry found that 92 percent of participants experience some seasonal mood and behavior change. These milder cases are called “subsyndromal SAD” and usually respond well to some recommended therapies.

A primary symptom of SAD and seasonal mood changes is an increased craving for foods high in carbohydrates such as bread and pasta and foods high in sugar. Irritability, fatigue, and social withdrawal are also common symptoms. The tendency to withdraw from social situations can create additional stress during the holidays when there is additional pressure to attend parties and gatherings. Holiday parties also expose us to foods high in carbohydrates that we may usually avoid, such as cookies and other desserts. Overindulgence in carbohydrates may result in weight gain, which can worsen other depression symptoms.

In addition to the changes in weather and light exposure, women often bear the brunt of holiday stress. Family gatherings and kids at home during winter vacation can result in overworking and increased fatigue. The pressure to shop for holiday gifts may also create additional financial burden for many families. Since women are more susceptible to depression and other moods disorders, the winter holidays and weather may be an especially challenging time of year.

Decreasing stress is an important strategy in treating and preventing SAD, especially for women. Maintaining a healthy lifestyle with adequate sleep, balanced diet, regular exercise, and moderate use of alcohol may reduce the symptoms of SAD. When additional help is needed, research has shown that light therapy can successfully treat symptoms. Light therapy usually entails at least a half-hour of daily exposure to a light box that provides intense, full spectrum light—much stronger than common light bulbs. For individuals who work at a desk, a desktop light may be helpful. Antidepressant medications such as selective serotonin reuptake inhibitors (SSRI) may also be effective in relieving symptoms and can be prescribed by family physicians. In severe cases of SAD, health care providers may recommend both light and medication therapy.

David E. Adson, M.D. is associate professor of psychiatry at the University of Minnesota Medical School. He is also associated with the University’s Women’s Health Center of Excellence. This column is an educational service of the University of Minnesota. Advice presented should not take the place of an examination by a health-care professional. For more health-related information, go to http://www.healthtalk.umn.edu/