How it is Contracted

Experts are not sure what causes SAD, but they think it may be caused by lack of sunlight. Lack of light may upset your sleep-wake cycle and other circadian rhythms. It may cause problems with a brain chemical called serotonin that affects mood. Just because the specific cause of seasonal affective disorder remains unknown it's likely that many mental health conditions, genetics , age, and perhaps most importantly your body's natural chemical all play a role in developing the condition.