Winter has long been associated with depression; in literature winter represents dormancy and death and the ending of life. Scientifically speaking there may be a clinical reason for this connection. Seasonal Affective Disorder (S.A.D.) is a type of depression that only occurs during the winter months. There are many different physiological causes, including a disturbance in the “biological clock,” which controls one’s sleep-wake patterns and other circadian rhythms, vitamin D deficiency, and lower serotonin and melatonin levels. The root cause, however, stems from a lack of light. During the winter months, there are fewer hours of daylight, and as a result, individuals who are more sensitive to light, or a lack thereof, suffer from S.A.D.

S.A.D. is more common in areas farther away from the equator where days are shorter and winter is longer. Although anyone can get S.A.D., women between the ages of 15 and 55 are more likely to be affected by it. Seasonal Affective Disorder may also have a genetic component, putting individuals with family members suffering from the disorder at a higher risk.

Like any form of depression, S.A.D. manifests itself differently depending on the person. However the most common symptoms are fatigue, hopelessness, moodiness, anxiety, increase in appetite, weight gain, trouble concentrating, social withdrawal, and irregular sleep patterns. If a person suffers from Seasonal Affective Disorder, some or all of these symptoms tend to develop in October or November and usually clear up by April or May.

For people suffering with S.A.D., there are several different treatments that can help, and as with most types of depression, some treatments may work better than others depending on the individual. Common treatment includes vitamin D supplements, antidepressants, talk therapy and light therapy. Light therapy is most often used in combination with other treatments and involves exposure to light for extended periods of time. Lights used in light therapy are brighter than indoor lights but not as bright as direct sunlight. Light therapy is thought to reset your circadian levels and, as a result, reduce depression. While antidepressants can have a long list of adverse side effects, light therapy is generally safe, although not always as effective in extreme cases.

Seasonal Affective Disorder plagues more than three million people in the U.S. every year. Like all forms of depression or mental illness, it is best to consult a doctor or psychiatrist for medical and psychological help. For those suffering from S.A.D., it is helpful to consider the words of Hal Borland: “No winter lasts forever; no spring skips its turn.”