Changes in mood are fairly typical for teens but when teens experience depression during the winter months, Seasonal Affective Disorder (SAD) may be the cause. According to the National Institutes of Health (NIH), SAD often begins during the teen years and strikes girls four times more often than boys. The symptoms of SAD are the same as those of depression, but only manifest themselves for a few months a year.
Two naturally occurring chemicals, serotonin and melatonin, are thought to be involved in SAD. When it is dark and days are shorter, melatonin, which is linked to sleep, is produced in greater quantities. An increase in melatonin can cause sleepiness and lethargy Serotonin production increases with exposure to sunlight, and low levels of serotonin are associated with depression. The shorter days and longer hours of darkness in the fall and winter can increase the level of melatonin in a teen’s body and decrease serotonin levels, thus creating the biological conditions for depression.
Approximately 6% of the population experiences SAD. Teens and adults with relatives who have had depression are more likely to experience SAD and studies have shown the rates of SAD to be seven times higher in areas further away from the equator.
It is important to talk to a doctor if you or your teen believes he or she has SAD. SAD can be treated by increased light exposure, light therapy medication and psychotherapy. For many people experiencing SAD, the depression lifts even without treatment, when spring arrives.