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The question

I think I have seasonal affective disorder. How do I know for sure?

The answer

Seasonal affective disorder (SAD), more commonly known as "the winter blues," is a type of depression that impacts about two to three per cent of the general population.

Many of us find that our mood and energy levels are affected by the weather: Warmer, sunnier days tend to lift our moods, while cold, rainy, dark days can make us feel gloomier. For a certain percentage of people, the weather (and in particular seasonal variations in light that come along with shorter days) has a more significant impact and can lead to the development of a particular subtype of clinical depression.

You may have SAD if you notice the following:

- A distinct seasonal pattern to your mood (i.e., very little or no depression symptoms during spring or summer months, when the days are longer)

- Persistently low, depressed mood that lasts for usually two to three months during winter months. November to February are the peak months.

- Depression symptoms (such as low mood, changes in appetite or weight, decreased energy or fatigue, sleep changes, avoidance of social situations) in the absence of other identifiable triggers or causes

- Improved mood if you are in a sunnier climate during the usual "high risk" winter months

We don't understand very well why some people are so much more affected than others by weather and sunlight, but there seems to be a stronger biological/genetic component than with other types of depression.

There are a number of very effective strategies that can help lessen the impact of SAD:

- Make a point to spend more time outdoors during peak light hours (10am to 2pm), even if it's only for 10 to 15 minutes during a coffee or lunch break.

- Arrange your home and work environments (if possible) to maximize your exposure to direct sunlight: Leave blinds and curtains open and try to be around windows that allow in natural light.

- By hypervigilant about taking care of yourself in the fall months, before the usual season dips in mood occur (i.e., exercise, eat a healthy diet, drink alcohol in moderation).

- Talk to a physician about the use of a light box; many people find that 10 to 20 minutes of artificial "light therapy," usually prescribed to be taken first thing in the morning, has significant benefit.

In addition to the above, approaches that are effective for general depression, such as cognitive-behavioural therapy from a psychologist or psychiatric medication treatment, are also of significant value.

Useful information on Seasonal Affective Disorder and light therapy can be found at the Mayo Clinic site.

Send psychologist Joti Samra your questions at She will answer select questions, which could appear in The Globe and Mail and/or on The Globe and Mail web site. Your name will not be published if your question is chosen.

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