"Seasonal Affective Disorder (SAD) is a form of depression that affects approximately 1 in 50 or just over 1 million people in the UK between September and April. It can be particularly severe during December, January and February. For some people, SAD is so disabling that they cannot function in winter without continuous treatment. Others may experience a milder version called sub-syndromal SAD or 'winter blues' which 1 in 8 of us experiences during the autumn and winter seasons." Click here to read about SAD