Using Light Boxes for Seasonal Depression

How to Use Light Therapy to Alleviate Seasonal Affective Disorder

Nov 9, 2009

SAD light therapy has been scientifically proven to help alleviate SAD. But how do light boxes work and what is the best way of administering light therapy?

Seasonal affective disorder affects one in eight people in the UK from its mildest form to its most crippling (“Seasonal Affective Disorder,” NHS, 2009). Symptoms include tiredness, depression, carbohydrate cravings, sleep disturbances and low motivation.

Research has shown that the symptoms of SAD are caused by a decrease in seratonin and the increase of melatonin within the brain. This is triggered by the dark winter months when days are short. Indeed, the Society for Light Treatment and Biological Rhythms (SLTBR) asserts that light therapy is the best treatment for SAD. But light therapy can also be used for jet lag, insomnia and shift working. With this in mind, how does the consumer use the light box effectively?

Blue Light Therapy

Professor Alan Bird, an eye specialist of the Moorlands Eye Hospital, discovered blue light receptors at the back of the eye are activated by blue light that in turn produces a hormone that blocks the seratonin-clearing chemicals associated with depressive symptoms. From this, an effective light box should include short wave lengths.

Sufficient brightness is also required for treatment. A frame of reference can be sought when understanding the unit “lux,” a measurement of brightness.

Equal importance is the Kelvin, or the colour of the light. High Kelvin or short wavelengths is bias towards the blue spectrum; low Kelvin or longer wavelengths is bias towards the red or yellow spectrum.

An effective light box imitates natural daylight, so will have a Kelvin temperature of around 5000k. Importantly, the light will have a bluish cast, but a special diffuser screen blocks out harmful UV rays, so the user may benefit from the blue light.

How to Use Light Boxes

A study conducted by the American Psychological Association, “Light Therapy for Seasonal Affective Disorder: A Review of Efficacy,” (Michael Terman et al, March 1989) found that light therapy was most effective when subjects received light therapy early in the morning. Anything from half an hour to two hours per day depending on the brightness of the light box alleviated symptoms.

An electronic devise known as a “ballast” converts the electrical current to the correct wavelength within the lamp safely. They come in two types:

The Best Light Box for Blue Light Therapy

Light therapy is an effective treatment for SAD, but purchasing the right product and knowing how to use it will increase the effectiveness of treatment. A light box that simulates daylight, but also contains short wavelength will activate the blue light receptors at the back of the eye that helps maintain the amount of seratonin in the brain. Sufficient brightness, of around 10,000 lux light therapy, will add effectiveness. Research has shown that receiving light therapy early in the morning reaps the best benefits.

Note: Although light therapy is a safe treatment, consultation with a GP or eye specialist is recommended prior to embarking upon light therapy.

The copyright of the article Using Light Boxes for Seasonal Depression in Natural Medicine is owned by Rachel Wills. Permission to republish Using Light Boxes for Seasonal Depression in print or online must be granted by the author in writing.