LONDON, England (CNN) -- When the days start getting shorter and colder, and the nights longer and darker, many people start to suffer from winter depression, or Seasonal Affective Disorder (SAD.) We outline some strategies for dealing with those winter blues.
Cheer up, you have a recognized medical condition
Don't worry, summer is only six months away.
It might seems like curious advice, but for many sufferers the effects of SAD are greatly exacerbated by the fact that they just can't understand why they feel so darned miserable, and blame themselves for their grumpiness rather than a genuine mood disorder.
Thanks, however, to the pioneering work of U.S. doctor Norman E. Rosenthal -- who coined the term SAD in 1984 -- it is now widely acknowledged that winter depression has a sound medical basis, involving changes in the body's mood centers brought on by shorter daylight hours and a lack of sunlight.
If anyone accuses you of being a surly misanthrope between the months of November to February, you can justify yourself with words to the effect of: "Sorry, but I'm suffering from a biochemical imbalance of my hypothalamus triggered by a melatonin deficiency in my pineal gland. So get off my back!"
Cheer up even more, you're one of many
One of the worst aspects of any form of depressive illness is the sense of utter isolation and loneliness it induces. There is thus some comfort to be drawn by SAD sufferers from the fact that you are surrounded by people who feel equally grouchy and nihilistic around this time of year.
In the UK, according to the SAD Association, 500,000 people experience some form of winter depression, while in Sweden doctors have estimated that 20 percent of the population -- almost 2 million people -- are affected. One of the earliest descriptions of SAD comes from the Sixth Century chronicler Jordanes who, in his Origin and Deeds of the Goths, describes the excessively gloomy winter disposition of the inhabitants of Scandza, or Scandanavia.
Let there be light
Without doubt the most effective clinically proven remedy for SAD is "light therapy," which has been shown to benefit some 80-85 percent of cases. Simple as it sounds this actually involves rather more than just turning on a light and sitting beside it for a while twiddling your thumbs as renewed cheer inexorably suffuses your being.
The average domestic or office light emits a paltry 200-500 lux (a lux is a unit of illuminance,) whereas a minimum of 2,500 lux is required to alleviate the symptoms of SAD. For the record, a clear summer's day can reach an intensity of 100,000 lux.
Fortunately, specially designed light boxes have been developed that emit precisely the right amount of illumination. These can be bought from specialist retailers and, at their most basic, cost around $190 (£100.) By sitting in front of one for a certain period each day -- 30 minutes to several hours, depending on the severity of your conditions -- symptoms gradually subside. Sadly, though, you won't be left with a suntan.
Drugs and therapy
While greater light exposure is far and away the best treatment for SAD, addressing as it does root causes rather than just symptoms, both anti-depressant drugs and psychotherapy have also proved helpful to sufferers, especially those with especially severe symptoms.
If you wish to go down this route you should seek advice from a medical professional, or else contact one of the many SAD support organizations that exist around the world (type Seasonal Affective Disorder help into an Internet search engine for an exhaustive list of such organizations.)
Move south (or north) for the winter
This may or may not be practical, depending on your circumstances, but studies have shown that the incidence of SAD increases dramatically the further north, or south, you go from 30 degrees of latitude.
The condition is virtually unheard of in the Tropics, on the other hand, and it therefore stands to reason that a move to anywhere in the vicinity of the Equator for the duration of the winter should go a long way towards improving your mood (although whether three months in Mogadishu will completely cure you of the blues is uncertain.)
Watch "Lawrence of Arabia" over and over again
Unlikely as it sounds, research has shown that winter depressives who watch films featuring warm, sunny, summery climates show demonstrable improvements in mood.
Anything with clear blue cloudless skies, palm trees and an absence of snow ploughs should do, although with its endless shimmering desert vistas and eye-watering three and a half hour running time, David Lean's 1962 epic "Lawrence of Arabia" probably offers the most intensive movie therapy available.
Watching cricket or golf can, apparently, have the same mood-enhancing effect. Over-exposure to snooker, darts and indoor bowling on the other hand, has been known to bring on a state of depressive, trance-like catatonia that, in severe cases, culminates in complete mental breakdown. E-mail to a friend
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