Seasonal Affective Disorder
How many of us have not turned our faces toward a nice afternoon sun in the depths of the gray winter months seeking what little light that can be gained?
We often leave lights on throughout our homes or even head south to a nice tropical location mid-winter, anything to get away and get a little more light.
For many people, this need for light can take on an even greater significance by treating "winter blues" or the potentially debilitating symptoms of a type of depression known as seasonal affective disorder or SAD.
Winter depression, such as SAD, and the winter blues, are a cyclical depression that is most often triggered by the onset of fall or winter as the daylight hours become shorter and shorter.
In rare cases, these same conditions can even develop during the summer months as well. Signs of this form of depression can include sadness, sleep difficulties, increased appetite and the craving of carbohydrate rich foods, weight gain,
lack of energy, irritability, anxiety, and problems with concentration. The symptoms in some people can be severe enough to interfere with daily activities, obligations, and overall quality of life for months on end. So
what can you do during those dark days when it is all that you can do just to get out of bed in the morning, and you find yourself overeating, skipping work, and feeling overwhelmed? The simple answer is to use a light therapy device.
Light therapy cannot be done with just any household lamp, but rather with specialized lights designed to help you enjoy life again. It has been used to treat forms of seasonal depression since the early 1980s and is now
considered standard treatment for seasonal mood disorders. There is mounting scientific evidence that this form of depression arises from abnormalities in how the body manages its circadian rhythms or biological clock.
Genetic factors may also be involved, but the evidence heavily favors the idea that changes in the day-night cycle induce biochemical changes that bring on seasonal affective disorder and depression, either mild or severe. Evidence shows that the
hormones melatonin and serotonin play a major role in regulating circadian rhythms, body temperature, hormone secretion, and sleep.
It is known that adequate light is vital to many aspects of healthy living and recent studies show that specialized photoreceptors in the eye turn a specific range of light into electrical impulses that are sent directly to the brain, triggering a reduction in melatonin production.
During the light starved winter months our bodies naturally produce more melatonin and less serotonin to the point of mood changes and depression. Exposure to bright light suppresses the sleep hormone
melatonin and at the same time increases the "feel good hormone" serotonin.
There are four keys to effective therapy:
Intensity. To work properly, the light you use must have the right intensity. Intensity is measured in Lux, which is the amount of light you receive at a given distance from a light source.
You should receive 10,000 Lux for at least 15 minutes, or 5,000 Lux for 30-45 minutes. This is 50-100 times the amount of light found in an average living room in the evening, while a bright summer day may be as high as 100,000 Lux.
Duration. Therapy sessions typically last from 15 minutes to several hours. We suggest starting in smaller blocks and working up to longer periods.
Timing. For most people, treatment is best used in the morning, after waking and allowing your eyes to adjust to normal room lighting. Using an intense full spectrum device at night can make it difficult to sleep and should be avoided.
Spectrum. Recent research has began to highlight the role that full spectrum or lighting with an enhanced blue range plays in melatonin production. Full Spectrum and scoptopically(blue) enhanced light that simulates daylight is not only more pleasant to the eye than warmer lights it is more effective.