With the arrival of fall soon upon us, the upcoming seasonal change means shorter days, changing weather and changing leaves. However, for some, this time of year can also mean a change in mood, as the affect of less exposure to sunlight can greatly alter one’s mental wellness during the colder months.

Seasonal affective disorder (SAD) is a condition in which a person feels depressed at a certain time each year, mainly in the fall and winter. The disorder is sometimes called "the winter blues."

Who is affected by SAD?

Women are more likely to be affected by SAD than men. Children and teens can also have SAD, but it usually starts during young adulthood.

People who work long hours inside buildings with few windows or during long periods of cloudy weather are most prone to develop SAD.

According to the National Alliance on Mental Illness, approximately 10 to 20 percent of the population suffers from mild winter SAD, and nearly 5 percent suffer from a more severe form of the disorder.

What are the symptoms?

The following are the most common symptoms of SAD. However, each individual may experience symptoms differently.

• Fatigue
• Trouble focusing
• Headaches
• Weight gain
• Irritability
• Anxiety
• Less interest in activities that usually make you happy

Always see your health care provider for a diagnosis.

What causes SAD?

The cause of SAD is not clearly known. It may be related to changes in the amount and intensity of sunlight throughout the different seasons.

SAD may also be related to changes in the brain's chemicals that occur with fewer daylight hours and less sun exposure. People make larger amounts of the hormone melatonin when days are shorter. This chemical has been linked to depression.

Treatment for seasonal affective disorder

Your doctor can provide specific treatment recommendations based on your needs and the following:

• Age
• Overall health
• Medical history
• Severity of the disease
• Your preference on treatment options

The treatments for "winter depression" often differ, and may include the following:

• Light therapy, also called phototherapy, involves the simple procedure of repeated sessions of sitting in front of a very bright light.
• You can also increase your exposure by taking long walks outdoors, especially on sunny days, or rearranging your home or workspace so that you are near a window during the day. The brighter the light, the more effective it is.
• Counseling sessions
• Antidepressant medications
• Regular exercise
• Stress management techniques