The end of day light savings got you down? As fall drifts on, the amount of day light dwindles and for some, so may your spirits. But before you chalk it up to your primal instinct to hibernate for the winter, learn more about seasonal affective disorder. Seasonal affective disorder (SAD) is described as mood disturbances, often manifesting as depression, that occurs in a seasonal pattern. Typically it occurs in the autumn and winter months, and remits in the spring and summer. In the US, approximately five percent of the population suffers from seasonal affective disorder with an increased incidence in the northern latitudes. And like most forms of depression, it affects women disproportionately with a reported female-to-male ration of 4:1. The symptoms of SAD are considered “atypical” of depression. There are some overlapping signs and symptoms with classic depression: irritability, difficulty with personal relationships, decreased energy and concentration. But in contrast, SAD frequently has unique symptoms of increased sleep, increased appetite with carbohydrate craving, and weight gain.
The cause of SAD is complex and multifactorial; however, current research suggests biologic mechanisms including circadian rhythm disturbances and light sensitivities. This make sense, then, why light therapy is uniquely effective for fall-onset SAD. Light therapy does not equal UV retail therapy (i.e. tanning beds). Tanning beds emit ultraviolet radiation, UV, which has not shown statistically significant improvement of depressive symptoms and should be avoided because of the potentially harmful effects. Therapeutic light therapy, on the other hand, is based on the amount of light perceived by the human eyes and brain, and is used with a UV filter. While you should discuss any symptoms of depression or SAD with your provider, light boxes can be purchased without a prescription. Research shows that in order for light therapy to be effective you:
- should be positioned about 12 to 18 inches from a white, fluorescent light source at a standard dosage of 10,000 lux for 30 minutes per day in the early morning (this is roughly equivalent to outdoor light about 40 minutes after sunrise).
- must be awake with your eyes open, but are not required to look directly into the light (eating or reading during the treatment is acceptable as long as the light enters the pupil).
- need at least one to two weeks of therapy for significant improvement in SAD and may require four to six weeks. Therapy should be continued until sufficient day light exposure is available (i.e. spring).
Some experts recommend certain lifestyle adjustments to prevent SAD symptoms: exercising more often, increasing light in the home or at work, practicing relaxation and stress management techniques, spending more time outside, and visiting sunnier, warmer climates. There’s lots of research and talk about vitamin D, but its role in depression is [so far] unclear. Cognitive behavioral therapy has also been studied and shows some improvement with SAD. If these remedies fail or should you prefer to consider medicinal treatments, antidepressants (particularly buproprion) are effective in treating SAD.
Where is spring already? Often, SAD will improve with the arrival of longer daylight hours. While SAD cannot necessarily be prevented, there are some things you may be able to do to stave off its effects. If you experience SAD (or are just not yourself this time of year), consider starting your therapy of choice as fall approaches and continue through until spring. Light up, carry on.