How light therapy can help seasonal affective disorder
Seasonal affective disorder and its milder form, the "winter blues," affect millions of Canadians. Find out how light therapy can help
‘Therapeutic’ lighting devices, which emit very bright artificial light, can be readily purchased for in-home use in Canada. They promise to lift mood and energy levels during our short-on-sunshine winters. Clever marketing, to be sure. But do they really deliver?
‘If you have mild symptoms [of depression], you might consider using light, in the same way that people use exercise,’ says Dr. Raymond Lam, a psychiatrist at the Mood Disorders Centre at UBC Hospital in Vancouver. (Studies have mostly been done on people with seasonal depression, which is much more serious than just the winter blahs.)
Seasonal depression, or seasonal affective disorder (SAD), is a form of clinical depression that affects up to one million Canadians in the fall and winter. Scientists haven’t determined the cause, but think the reduction in sunlight during the winter disrupts some people’s internal clock, and may alter the levels of certain chemical messengers in their brains. In a study published in 2006, Lam compared the effects of light treatment and the antidepressant fluoxetine (Prozac) in patients with SAD. Light therapy was as effective as the drug, and patients experienced fewer side effects. Research is examining if light exposure can help people with non-seasonal depression and other health problems where the biological clock is disturbed, such as attention deficit and hyperactivity disorder (ADHD).
Although bright-light boxes have few side effects, consumers need to be cautious when using them, because the industry is unregulated. Here are some suggestions from the experts.
Choose a device that:
‘ emits white light rather than blue, and has a UV filter
‘ uses a fluorescent bulb (although new research is indicating that LEDs may be just as effective)
‘ emits 10,000 lux, the level of illuminance most widely tested
‘ is approved by the Canadian Standards Association (CSA).