If this winter you are feeling blue, gaining weight and waking up tired, even though you might be sleeping more, you may have seasonal affective disorder. Seasonal affective disorder, or SAD, is a type of winter depression that affects an estimated half a million people every winter. It is caused by a biochemical imbalance due to the shortening of daylight hours and the lack of sunlight in winter.
Ron Zec, Ph.D., associate professor of neurology and psychiatry at the SIU School of Medicine, explains the symptoms.
Both men and women can have SAD, but it is more common in women and it occurs more often in young adults, age 20 to 40. The disorder is more prevalent in the months of December, January and February when the days are shortest.