SAD is becoming more common. (Screenshot from Translucent Confrontations/Wordpress)

SAD is most common in the winter months when temperatures begin to decrease and people feel forced to hibernate in their homes. According to the U.S. National Library of Medicine, SAD is more common in females than in males. Symptoms may begin in teenage years or young adulthood. Teenshealth states that 6% of people experience SAD every year. 

While symptoms are very similar to those of other forms of depression, it is important to recognize the differences in order to treat SAD properly and immediately.

According to the American Psychiatric Association, symptoms include fatigue, lack of interest in activities, social withdrawal, cravings for foods high in carbohydrates and weight gain.

There may be extreme cases where a person experiences all symptoms at once. It is also possible for a sufferer to experience symptoms in the opposite form, such as weight loss instead of weight gain.

Other symptoms, according to U.S. National Library of Medicine, include hopelessness, less energy and irritability. SAD can sometimes become long-term depression, and bipolar disorder or suicidal thoughts are possible. Because there are no tests for this form of depression, it is important that you study your symptoms. 

Seasonal Affective Disorder can be attributed to the biochemical imbalance in your brain that is caused by the gloomy winter days and lack of Vitamin D. According to the American Pyschiatric Association, humans can experience a change in their internal clock as days become shorter -- therefore their days just "seem off."

Melatonin (the sleep-related hormone) levels increase in the dark, which may leave people drowsy. On the other hand, a decrease of serotonin due to lack of natural light causes a loss of energy. In short, the dark days of winter are the main cause of development for SAD, according to the National Library or Medicine. 

Because symptoms could also be related to other forms of depression, hypoglycemia or mononucleosis, it is important to get a medical check up before any treatment. Doctors may subscribe increased light exposure, psychotherapy, meditation or photo therapy, where a sunlight simulator is placed in front of the patient for 45 minutes each day. Sometimes just walking outside or working near a window can help treat this form of depression. 

To avoid stumbling into the pitfalls of SAD, spend some time outside with the people you love as opposed to hibernating by yourself. Being around people and being exposed to sunlight -- even if it's hidden behind clouds -- is the best way to keep your seratonin and melatonin levels steady.

Reach Staff Reporter Beatrice Verhoeven here. Follow her on Twitter.