What is SAD?
SAD (Seasonal Affective Disorder) is a type of winter depression which affects millions of people every winter between September and April, in particular during December, January and February. SAD is caused by a biochemical imbalance in the hypothalamus due to the shortening of daylight hours and the lack of sunlight in winter. For many people SAD is a seriously disabling illness, preventing them from functioning normally without continuous medical treatment. For others, it is a milder condition, causing discomfort, referred to as sub-syndromal SAD or winter blues.
