How to know if you’re suffering from seasonal affective disorder
Find out more about Seasonal Affective Disorder

What is seasonal affective disorder?
Do you find yourself getting depressed during the holiday for no clear reason? Are you more moody, depressed, or tired when the weather changes? Seasonal affective disorder (also called SAD) is a kind of depression that follows the seasons. Winter depression is the most common type of SAD. A less common type of SAD, known as summer depression, usually begins in the late spring or early summer. may be related to changes in the amount of daylight during different times of the year.
Who suffers from SAD?
SAD is more common in northern geographic regions that don’t receive as much sunlight. Up to half a million people in the United States may have winter depression. SAD is more common in women than in men. SAD usually doesn't start in people younger than 20 years of age.

Diagnosing SAD

Although your symptoms help clarify your diagnosis, not everyone with SAD has the same symptoms. Common symptoms of winter depression include a change in appetite, especially a craving for sweet or starchy foods, weight gain, a heavy feeling in the arms or legs, a drop in energy level, fatigue, a tendency to oversleep, difficulty concentrating, irritability, increased sensitivity to social rejection, and avoidance of social situations
Summer depression symptoms include poor appetite, weight loss and insomnia. Either type of SAD may also include some of the symptoms that are present in other forms of depression, including feelings of guilt, ongoing feelings of hopelessness, a loss of interest or pleasure in activities you used to enjoy, and physical problems, such as headaches.
Symptoms of SAD keep coming back year after year, and they tend to come and go at about the same time every year. The changes in mood are not necessarily related to obvious things that would make a certain season stressful, such as being unemployed during the winter.

Is there a treatment for SAD?

Yes. Since winter depression is probably caused by your body's reaction to a lack of sunlight, light therapy is one option for treating winter depression. If your doctor suggests you try light therapy, you may wear a light visor that you wear on your head like a cap. The procedure consists of sitting in front of the light box or wearing the light visor for a certain length of time each day. Generally, light therapy takes about 30 minutes each day throughout the fall and winter, when you're most likely to be depressed. If you respond well to light therapy, you'll continue using it until enough sunlight is available. Stopping light therapy too soon can allow the symptoms to come back. Warning: tanning beds shouldn't be used to treat SAD. The light sources in tanning beds are high in ultraviolet (UV) rays, which harm both your eyes and your skin. Your doctor may also want you to try a medicine or behavior therapy to treat your SAD. If light therapy or medicine alone doesn't work, your doctor may want you to use them in conjunction.