Light is vital to our well being, the long hours of darkness and a lack of daylight in the winter months affects upwards of 2 million people in the form of SAD (Seasonal Affective Disorder). The milder form of the condition (Sub SAD) sometimes known as the "winter blues" can affect upwards of ten million people in the UK alone. For many people SAD is a seriously disabling illness, preventing them from functioning normally without continuous medical treatment.

Health professionals have come to realise that a lack of natural light in the Autumn and Winter allied with our modern lifestyle of commuting to and from work in the dark and working in poorly lit office environments has led to SAD becoming more prevalent in many more people than in the past when more people worked outdoors. SAD can affect people of any age group, but is usually onset between the ages of 18 to 30.

When trying to treat SAD the common symptoms related to Seasonal Affective Disorder should be diagnosed:

Symptoms

• Depression
• Despair
• A craving for carbohydrates
• Weight gain
• Sleep Problems
• Reduced interest in Sex
• Behavioural problems (more prevalent in young people)
• Lethargy
• Lack of energy (Fatiqued)
• Irritabile and a desire to avoid social contact

SAD symptoms usually reoccur regularly each winter, starting between September and November and continuing until March or April; a diagnosis can be made after 2 or more consecutive winters of symptoms. In sub-syndromal SAD, symptoms such as tiredness, lethargy, sleep and eating problems occur, but depression and anxiety are absent or mild.

SAD symptoms disappear in spring, either suddenly with a few weeks of hypomania/hyperactivity, or gradually, depending on the intensity of sunlight in the spring/early summer. In summer SAD, symptoms may be related to excessive heat rather than light and may include irritability and lethargy rather than oversleeping and overeating.