Exposure to bright light may help lighten the symptoms of major depression. In one study, Dutch researchers included 89 people with major depressive disorder (MDD) who were ages 60 and older. The participants were randomly assigned to get an hour of exposure every morning for three weeks to either bright-light treatment or a dim red light, which was used as a placebo.
The researchers measured the subjects' depression at the beginning of the study, after three weeks of treatment and three weeks after the end of the treatment. The bright-light group had a 7 percent better improvement in depression scores at the end of the treatment compared with the placebo group. Three weeks after the end of treatment, symptoms kept improving in the bright-light group but not the placebo group.
In addition, at the end of treatment the bright-light group had a better improvement in sleep efficiency (the amount of time they spent actually sleeping after they fell asleep) than the other group, and they got out of bed faster after they woke up.
Bright-light treatment may be an important supplemental treatment for people who do not fully respond to antidepressant treatment.
Source: Archives of General Psychiatry, Volume 68, page 61, January 2011