What is light therapy?
Just as it sounds, light therapy involves exposing patients to additional light in their environment through specialized light devices. It is generally used to treat seasonal affective disorder (SAD), which is a winter-induced depression believed to affect some 5% of adults.
Light therapy techniques: How does light therapy work?
Participants in light therapy purchase a special lamp that emits a type of bright light in a spectrum believed to be helpful. (Regular lamps won’t work, and you should consult a therapist before trying it.) Patients then undergo home therapy sessions that are spent sitting or laying under the light. Light boxes typically emit anywhere from 2,500 to 10,000 lux (a measurement for brightness), and the degree of light is typically adjusted for each person. Patients use them for 30-60 minutes a day on average, depending on the person and the severity of their depression.
Is light therapy effective?
Few studies have examined the effectiveness of light therapy, so we would consider it an experimental therapy that participants must take on faith more than science. One study published in the American Journal of Psychiatry in 2006 assigned 96 SAD patients to receive either light therapy plus a placebo capsule or a placebo light treatment plus 20 mg of fluoxetine (prozac) each day. Patients in both groups showed overall improvement with time, with no significant differences in outcome. Yet light therapy seemed to provide faster results, and was not associated with the adverse side effects of drugs. (Cassinos-Carr, 2012)
However, seasonal affective disorder is itself a controversial diagnosis. Although there’s no doubt that some people experience seasonal depression and that winter depression rates are slightly higher in colder climates such as Montana than in Florida, there’s still a great deal of debate about precisely what causes this. Some research has indicated that the lack of sunlight during the winter months that people who live in such climates experience may disrupt their biochemistry, thus leading to changes that result in depression. This is where the idea for light therapy comes from. But even if you accept this hypothesis (and not all scientists do), it takes another leap of faith to assume that 30 minutes daily under bright artificial light would correct this enough to achieve a significant benefit.
So overall, the science behind light therapy isn’t particularly convincing, although we also can’t definitively say that it doesn’t work.
The benefits of light therapy
- Whether it works or not, at least light therapy poses no conceivable harm to patients, so there’s little risk in trying it out.
- Even if it is a placebo, placebos frequently work and can be quite effective. If it’s something participants enjoy or find relaxing or if they think it helps, then it helps.
The downsides of light therapy
- Light boxes can cost several hundred dollars, and frequently are not covered by insurance. Bulbs may also burn out and need to be replaced.
- It can be time consuming. You’ll need to set aside a time each day for a treatment session.