All about light-box therapy

• Light-box therapy can be an effective treatment for a range of sleeping disorders, including insomnia and seasonal affective disorder.
• Light-box therapy entails daily exposure to high-intensity light.
• There are a few kinds of light boxes, and they vary in price and can be purchased through various online vendors.

Light-box therapy, sometimes just called light therapy, is a method of treating several different sleep disorders, specifically insomnia, delayed sleep-phase syndrome (DSPS), advanced sleep-phase syndrome (ASPS) and jet lag.  It is also an effective method of treating seasonal affective disorder (SAD) or “the winter blues.”

DSPS is the most common sleep disorder involving circadian rhythm (your body’s natural clock).  This disorder occurs when a person’s body clock is running later than it should be, which results in feeling tired/falling asleep and waking up very late in relation to life’s daily cycle. People with DSPS generally sleep the same number of hours as those who don’t have the disorder; they just fall asleep out of sync with daily life patterns.    Teenagers and young adults are generally the candidates for DSPS.

ASPS is at the opposite end of the spectrum.  This disorder affects a person’s body clock by having early-onset sleep and early-morning waking times in relation to life’s daily cycle.  ASPS primarily affects older people, not allowing them to sleep past pre-dawn hours (3 or 4 A.M.).  Like DSPS, those afflicted with ASPS generally sleep the same amount of hours as those who are not afflicted; they just sleep out of sync with daily life patterns.
Jet Lag seems to be a more frequently occurring condition with the increasing availability of air travel.  Jet lag is characterized by sleepless nights and extreme fatigue during the daytime caused by crossing several time zones, which puts a person’s sleep-wake schedule out of sync with local time.  Jet-lag symptoms can be alleviated by using or avoiding bright light at various times of the day. 

Seasonal affective disorder is a condition in which a person feels depressed at certain times of the year.  Most people experience SAD in the fall and winter months when days become shorter and there is less sunlight.  The cause of SAD is not directly known.  It is speculated to be related to the amount and the intensity of sunlight in different seasons.

Light therapy treats the mentioned disorders by exposing the user to a special type of light that is much brighter than a lamp or light fixture found in your home.  The light comes from a box that contains fluorescent (not ultra-violet/full-spectrum) lights.  Light therapy is only available through a prescription by your doctor.  To use light therapy, the user simply sits a prescribed distance from the light box.  The amount of exposure needed depends on the intensity of light used.  Time spent with the light box ranges from 30 minutes to 2 hours.  Light intensity ranges from 2,500 lux to 10,000 lux (10,000 lux is around 20 times as bright as normal indoor lighting).  Most users are prescribed 10,000 lux for 1 hour upon awakening in the morning. Light therapy for SAD is generally used in fall and winter months and discontinued in the spring.  When starting light therapy, the user’s initial response determines whether or not an adjustment in the time or intensity of the light is needed. Most users respond to the treatment within 3 to 5 days, but they may relapse into depression if 3 or more consecutive days of treatment are missed.

The most common side effects of light therapy are headache, eye strain and nausea.  Fatigue may take place in the first week of use due to changes in sleep-wake patterns, but this side effect normally subsides within the first week of use. 

Light boxes are available for purchase on the internet and come in a variety of sizes and portability options.  Prices for light boxes range from around $100 to $400 or more.  When purchasing a light box be aware of manufacturers that market inexpensive light boxes and devices that have not been researched for effectiveness or documented for safety.  The safest light boxes have fluorescent, not full-spectrum or ultra-violet light.


Key Words: light box, therapy, insomnia, seasonal affective disorder, sleeping, prescription, sleep phase, ultra-violet