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Seasonal Affective Disorder (SAD)


Seasonal affective disorder (SAD) is a specific type of depression thought to affect around 2 million people in the UK and 12 million people across Northern Europe. It can affect people of any age, including children, although symptoms are most likely to begin between the ages of 18 and 30. Women are reported to be three times more likely to be affected than men.

SAD is sometimes known as ‘winter depression’ or ‘winter blues’ as symptoms tend to appear as the days grow shorter during the autumn with the depression being at its most severe during the months of December, January and February. As the days grow longer, in the spring, symptoms start to improve and usually disappear completely during the summer months.

What causes SAD?

SAD is thought to be related to lack of daylight exposure and the effect that this has on some of the brain’s chemicals and hormones. The exact nature of this effect is not fully understood, but one theory is that light stimulates the part of the brain called the hypothalamus which controls mood, appetite and sleep and in some people insufficient sunlight results in a disruption of these processes, in particular:

  • The production of the hormone melatonin (the hormone that makes you sleepy)
  • The production of the hormone serotonin (the hormone that affects your mood)
  • The body’s circadian rhythm (internal body clock)

What are the symptoms of SAD?

  • Lack of energy
  • Lack of motivation
  • Sleep problems - finding it hard to stay awake during the day, but having disturbed nights
  • Feeling depressed – sad, low, weepy, guilty, hopeless, apathetic, numb
  • Feeling anxious – unable to cope with everyday stresses
  • Poor concentration
  • Loss of libido
  • Overeating – particularly carbohydrates
  • Being more prone to illness – a lowered immune system

Once someone has experienced two or three winters of such symptoms a GP may diagnose them as suffering from SAD.

Moving Out of SAD

Many people make their own diagnosis and treat themselves, but talking to your GP will give you a proper diagnosis, further information and medically supervised treatment options.

What sort of treatment is there? As with any type of depression the following may all be helpful in reducing or controlling symptoms:

  • Spend time outdoors in natural sunlight every day
  • Sit near a window when you are indoors
  • Make your home environment as light and airy as possible
  • Exercise regularly (experiment, find something that you enjoy doing)
  • Relaxation (maybe a good book or a film)
  • Rest (try to get into a regular sleep pattern – going to bed and getting up at the same time each day)
  • Eat a healthy, balanced diet
  • Spend quality time with friends or family
  • Explain how SAD effects your moods to family and friends so that they are more able to understand and support you
  • Cognitive behavioural therapy
  • Counselling
  • Antidepressants may be prescribed by your GP to help relieve symptoms
  • Light therapy*

*Many people suffering from SAD find the use of bright light therapy helpful. This involves sitting in front of a special light box for a specific period each day, usually every morning. Average use is for one or two hours per day. Several studies have concluded that light therapy can help relieve symptoms by mimicking the effects of natural sunlight and helping to rebalance the levels of melatonin and serotonin in the body.

There are many types of light box on the market and it is best to do some research before considering purchasing one. Your GP should be able to recommend a suitable reliable product and there are also approved SAD lighting suppliers registered with the Medical Devices Agency. More detailed information on such products can be found through some of the sources listed below.

It is always best to check with your GP as light therapy may not be suitable for you if you have an eye problem, have epilepsy or are taking certain types of medication, such as antidepressants. Occasionally people may suffer side effects such as irritability, headaches or in rare cases nausea.

Getting Support

The Wellbeing Support Services are available for students at the University of Warwick:

Medical support can be obtained through your GP.

Useful sources for information on SAD: (Search SAD) (Search SAD)

Self-help References

Winter Blues: Everything You Need to Know to Beat Seasonal Affective Disorder. Norman E. Rosenthal The Guildford Press

Seasonal Affective Disorder for Dummies. Laura L. Smith and Charles H. Elliot (2007). Wiley Publishing Inc.

The Light of Day: A Mindbody Approach to Overcoming Seasonal Affective Disorder. Lawrence Hayes (2008) Trafford Publishing

Help is on the Way: Saying Farewell to Seasonal Affective Disorder. Raymond Bloom (2012) Ellipsis Books

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