While many individuals dealing with depression may feel the effects year round, there is also a type of depression that manifests itself during certain times of the year. Seasonal affective disorder (SAD) tends to present symptoms in those suffering from the disorder during the winter months — typically when days are shorter and light levels are low. While anyone can develop seasonal affective disorder, it is most common in women, with the majority of people seeing symptoms before the age of 21.
Mental health professionals differentiate SAD from depression based on if symptoms occur on a cyclical basis (seasonally, yearly, etc). Symptoms include anxiety, guilt, suicidal thoughts, and general hopelessness. Other symptoms may include decreased energy, weight gain, poor immunity, trouble with relationships, changes in sleep, and difficulty concentrating. Cognitive behavioral therapy and light therapy are considered to be most effective treatment options.