In northern countries, light deficiency during fall and winter affects a significant number of people. For some, symptoms are quite severe during this period and subsequently disappear with the arrival of spring. This may point to a condition known as seasonal affective disorder – or SAD. In some cases, the symptoms of depression progress to a point where they can even lead to suicidal thoughts.
What is SAD?
Seasonal affective disorder is a form of depression associated with a lack of natural light. According to experts, an estimated 3 to 8 percent of adults living in northern climates – mostly women – are affected by the condition.
While the specific mechanisms involved in SAD are not yet clearly understood, the disorder is believed to be caused by a biochemical imbalance in the brain related to melatonin, a hormone that plays a central role in biorhythms and mood regulation. In addition, a low production of endorphins and serotonin in the brain may also contribute to SAD.
As is the case with all forms of depression, SAD is caused by an imbalance in the chemicals that take part in transmitting messages in the brain. In no way is it considered a sign of weakness or incompetence. It is rather a recognized disorder that returns year after year during the same period.
Symptoms of SAD
In Canada, symptoms of SAD generally appear in October and disappear in April or May; they may also spontaneously cease during a vacation to a sunny destination. The most common symptoms are as follows:
- Chronic fatigue and daytime sleepiness;
- Irritability or sadness, loss of interest and lack of initiative;
- Poor concentration;
- Decreased libido;
- Hypersomnia (the need to sleep excessively);
- Increased appetite, sometimes accompanied by weight gain.
If you think you may be suffering from SAD, please consult a health professional to obtain an accurate diagnosis and appropriate treatment specific to your situation.
Since SAD is caused by a lack of light, sufferers generally need to increase their exposure to it in order to regain their energy. People with mild symptoms should go outside daily for approximately one hour, during the sunniest period of the day. Exercise, particularly when it is performed in natural light, also has an antidepressant effect.
For those with more pronounced symptoms, there are treatments such as psychotherapy, light therapy, dawn simulators and antidepressants.
Studies have shown that luminotherapy (or phototherapy) helps to significantly reduce symptoms. It consists in exposure to a bright light from a lamp with an intensity of 10,000 lux (unit measuring the level of luminance), which contains the full spectrum of the sunlight – or ultraviolet rays. The length of exposure depends on the intensity of the light cast by the lamp used.
Artificial dawn simulation
Artificial dawn simulation is another form of phototherapy that involves reproducing the normal conditions of awakening by simulating a natural sunrise situation. In more concrete terms, this simply entails replacing your regular alarm clock with a dawn simulator programmed to gradually start producing light at the desired time.
If you have questions about SAD and how to treat it, talk to your pharmacist. He’s there to help!