Light therapy is sometimes used to treat insomnia and other sleep disorders. By using dawn simulator lamps and light boxes, light box therapy helps to reset the body’s internal clock and relieve sleep disorder symptoms.

Light Therapy and Circadian Rhythm Disorders

An area of the brain known as the suprachiasmatic nucleus (SCN) controls the body’s internal clock. The SCN controls the body’s circadian rhythms, which affect alertness, body temperature and hormone levels.

A typical circadian rhythm lasts approximately 24 hours. Shifts in light intensity control circadian rhythms. Sunrise triggers alertness, while sunset and darkness trigger sleepiness.

People with circadian rhythm sleep disorders have internal clocks that are out of sync with daylight hours and activities. Circadian rhythm sleep disorders include delayed sleep phase disorder, which causes people to fall asleep and wake up later than most people, and advanced sleep phase disorder, which causes people to fall asleep and awaken earlier than normal.

Circadian rhythm sleep disorders can cause daytime sleepiness, irritability, poor work and academic performance, and interfere with mental functioning.

Light box therapy treats circadian rhythm disorders by using bright light to reset the body’s internal clock. The goal is to bring abnormal circadian rhythms into harmony with normal sleep/wake cycles.

In addition to treating circadian rhythm sleep disorders, light therapy treats jet lag, helps shift workers adjust to new sleep schedules and relieves symptoms of seasonal affective disorder.

Light Therapy Boxes and Dawn Simulator Lamps

Light therapy involves more than just turning on the lights in your house. Instead, light therapy uses special lamps that emit a very intense light. This light therapy can be delivered in several different ways.

Many people use a light therapy box. Treatment involves sitting in front of the box, so the person is exposed to the light. People should not look directly at the light, but the light should reach the eyes.

Light therapy desk lamps provide the same high intensity as a light therapy box, but look like ordinary desk lamps. Light visors resembling sun visors allow people to move around during light therapy.

Dawn simulator lamps mimic sunrise and sunset by gradually increasing or decreasing the brightness of the room. Dawn simulator lamps help people adjust to new sleep/wake cycles, and are sometimes used by travelers to combat jet lag.

Light Therapy Alternatives?

Tanning beds are not an alternative to light therapy prescribed by a doctor, and can damage your skin. Likewise, home-built light therapy boxes can jeopardize your health. Instead, ask a doctor to recommend a safe and effective light therapy device.

Light Box Therapy Side Effects

Light box therapy is not associated with serious side effects. However, some people may experience:

  • Dry mouth
  • Eye strain
  • Headaches
  • Irritability
  • Nausea
  • Sleep problems.

Some people may not be good candidates for light therapy. Talk to your doctor if you:

  • Are taking a medication or supplement that causes light sensitivity
  • Have a history of skin cancer
  • Have a medical condition that makes your skin sensitive to light
  • Have bipolar disorder, since light therapy may trigger the onset of mania
  • Have any eye condition, such as cataracts or glaucoma.


Advameg, Inc. (2010). Light therapy. Retrieved October 11, 2010, from

American Academy of Sleep Medicine. (2006). Bright light therapy. Retrieved October 11, 2010, from

Gooley, J. (2008). Treatment of circadian rhythm sleep disorders with light. Retrieved October 11, 2010, from

Mayo Clinic. (2010). Light therapy. Retrieved October 11, 2010, from

 Posted on : June 12, 2014