A Newsweek report examines the benefits of blue-blocking glasses on sleep and bipolar disorder, and details the research that shows the role of light in controlling the circadian rhythm.
In 2009 study in Chronobiology International, Dr James Phelps and a colleague found that 50 percent of 20 bipolar patients experiencing insomnia had significant improvements in sleep after wearing blue-blocking glasses. The majority of those who responded showed not just small but dramatic improvements.
Other studies have shown that exposing bipolar patients to actual darkness during the nighttime can have similar results; one 2005 paper found that putting 16 bipolar patients in darkened rooms for 14 hours per day greatly improved their manic symptoms. But actual darkness is much more difficult to obtain, and more disruptive to life.
Studies have also shown that light can act as an antidepressant. One study in JAMA Psychiatry in January found that subjecting patients to bright light therapy was as effective at improving (unipolar) depression as the antidepressant fluoxetine, but with fewer side effects. And exposure to light can also help prevent the depressive phase of bipolar disorder, says Francesco Benedetti, a psychiatrist at San Raffaele Hospital in Milan uninvolved in the present study.
There is still much to be learned about dark and light therapy, but some psychiatrists are ready to recommend these techniques and blue-blocking glasses. “When you have a low-risk, almost no-cost treatment with high efficacy, it’s time to just use it,” Phelps says.