Beat the Winter Blues with Light Therapy
New research suggests that easing seasonal affective disorder (SAD) through light therapy could be easier than previously thought, thanks to smaller and more efficient light-producing devices.
Bright light therapy typically involves sitting in front of a light box for 30 to 60 minutes every morning. But light boxes are cumbersome and use a lot of electricity, leading some researchers to try designs using light-emitting diodes (LEDs) instead. LEDs are smaller, lighter, and more energy-efficient than the light bulbs used in conventional light boxes. They are also able to emit the specific light wavelengths that humans are most responsive to.
The latest study used a device called a "Litebook," which is made with 60 LEDs producing 1,350 lux. The people with SAD who participated in the study were randomly assigned to light therapy or placebo.
After four weeks of treatment, about 57% of the Litebook users had no SAD symptoms, compared with 11% in the placebo group. In addition, the average scores on tests used to measure SAD symptoms improved more in the light therapy group than in the placebo group.
(PH Desan, AJ Weinstein, EE Michalak et al. A controlled trial of the Litebook light-emitting diode (LED) light therapy device for treatment of Seasonal Affective Disorder (SAD) BMC Psychiatry 2007;7:38.)