Seasonal affective disorder (SAD)

Also known as winter depression. Many people suffer mood changes during the winter months which may even be serious enough to qualify as depression. Triggering factors for SAD are generally given as short daylight hours and low light levels during the “dark season”. Other (endogenous) factors must also be considered as the causes of winter depressions. Phototherapy with very bright light helps in many cases. Sufficiently bright light during the day can also prevent the onset.