Light Bulbs to Use for a Person With SADD

SADD (Seasonal Affective Depression Disorder) or SAD (Seasonal Affective Disorder) are also known as winter depression, because it commonly begins during the fall in response to shorter daylight hours. Light therapy is the most common form of treatment for SADD; however, special lights are needed to be effective.

Intensity

• Ordinary household light fixtures are insufficient for SADD therapy. The average incandescent or fluorescent light fixture delivers only about 50 to 300 lux (the scientific unit of light intensity), not nearly intense enough to provide effective treatment. The ideal light bulbs for treatment of SADD are bright white fluorescent lights which deliver approximately 10,000 lux. This approximately duplicates the intensity of full early morning daylight. Incandescent lights are less desirable because their small point source translates to a higher risk of retinal damage.

Color Temperature

• Color temperatures for light bulbs used to treat SADD should be between 3,000 and 6,500 degrees Kelvin for maximum effectiveness. The lower color temperature bulbs produce "softer" white light and less glare. Bulbs with higher color temperatures produce a "colder" skylight hue. Some people prefer full-spectrum lighting because it most closely resembles natural daylight; however, general scientific consensus is that full-spectrum lights are not necessary to achieve effective results.

Positioning and Safety

• The light bulbs should be installed in a special light box directed toward the patient with a downward slant, so that maximum light enters the retina and hits the light receptors of the eye. The patient's eyes should remain open, but staring directly into the light box is not advised. In fact, many patients engage in other activities, such as reading, during a light therapy session. Commercial light boxes feature diffusing lenses which provide protection against UV radiation as well minimizing the risks of electrical shorts and hot spots.