CHAPEL HILL, N.C., April 5 (UPI) -- North Carolina scientists said light therapy is as effective as drugs to treat some forms of depression, including seasonal affective disorder.
The team from the University of North Carolina at Chapel Hill reported in the American Journal of Psychiatry that they reviewed 20 randomized, controlled studies previously reported in the scientific literature.
Some studies of light therapy were not well-designed, said lead author Dr. Robert Golden, fueling controversy over the approach.
Once those studies were thrown out, he said, it was clear light therapy was an effective treatment for depression, including SAD, which occurs when natural light diminishes during the winter.
Light therapy consists of using bright artificial light. There is also "dawn simulation," which attempts to simulate an earlier dawn and the intensity of light during summer months.
"The effect size of the light therapy intervention in our meta-analysis was comparable to what has been described in the clinical literature for conventional medications to treat depression," Golden said. "The findings are as strong or as striking."